NREL 5-MW reference turbine - CP, CQ, CT Coefficients

Wind & Water Rotor Aerodynamics
41

Dear Jason,

I tried to implement a BEM code in MATLAB, using the Distributed Blade Aerodynamic Properties of the 5MW NREL wind turbine (Table 3-1 in the 5MW NREL reference pdf: nrel.gov/docs/fy09osti/38060.pdf) and the airfoils data. I find the maximum power coefficient of Cp_max=0.486 at TSR=7.82 and Pitch=0.0°, which are slightly off what is in the pdf reference (Cp_max=0.482 and TSR=7.55). Here is a plot of Cp with TSR and Pitch angle.

CpTSRPitch.png

I have two questions:
_ Is this tiny difference comes from the number of blade nodes taken?
_ Are those results that I found make sense to you?

42

Dear Younes,

Yes, these results are quite similar to the ones generated by NREL. Differences could be the result of discretization (which could easily checked by studying the convergence with increasing number of nodes) or by differences in the underlying BEM assumptions (more difficult to assess).

Best regards,

43

Dear Jason,

Thank you so much for the reply. I am wondering if there is a Cp table for the 5MW NREL wind turbine that we can use, or should we compute it ourselves? I see that WT_Perf is not available anymore.

Kindest regards

Younes

44

Dear Younes,

The Cp table for NREL 5-MW baseline wind turbine is available in one of the earlier posts in this forum topic above.

Best regards,

45

Dear Jason,

Thank you for the tables. I am interested in looking at the variation of the Cp in the table in the different regions. From the 5MW NREL documentation, in region 3, the pitch angle goes up to 25 degrees. But in the CpVersusTSR&Pitch_WT_Perf.xlsx table, the Cp table is limited to 5 degrees at maximum. Is there an open-source software like WT_Perf to compute it with a desired pitch angle range and TSR range?

Sorry for the inconvenience

Kindest regards

Younes

46

Dear Younes,

The standalone driver for AeroDyn (uncoupled from OpenFAST) can be used as a replacement for WT_Perf. The CCBlade module of the systems engineering tool WISDEM can also be used.

Best regards,

47

Dear Jason,

Thank you for the precise reply. I use AeroDyn as suggested, but I still have the same issue: I don’t find the Cp=0.48 at TSR_opt=7.55 for pitch=0°. The maximum Cp I get is 0.46 as you can see in the figure below (from AeroDyn):

AeroDYN.PNG
AeroDYN.PNG645×513 19.5 KB

I tried to change the nodes in AeroDyn_blade.dat, replacing them with the ones taken from WT_Perf input file. But I still can’t reach a power coefficient of 0.48. I don’t know what I am missing to get the right values. Do you have any suggestions please?
Here is my DRV input file:

-----  AeroDyn Driver v1.00.x Input File  --------------------------------------
NRELOffshrBsline5MW_Onshore_AeroDyn15.dat
-----  Input Configuration  ----------------------------------------------------
FALSE          Echo            -  Echo input parameters to "<rootname>.ech"?
"NRELOffshrBsline5MW_Onshore_AeroDyn15_Test01.dat"    AD_InputFile    -  Name of the primary AeroDyn input file
-----  Turbine Data  -----------------------------------------------------------
          3   NumBlades       - Number of blades (-)
        1.5   HubRad          - Hub radius (m)
    90        HubHt           - Hub height (m)
    -5.0191   Overhang        - Overhang (m)
         -5   ShftTilt        - Shaft tilt (deg)
        -2.5  Precone         - Blade precone (deg)
-----  I/O Settings  -----------------------------------------------------------
""            OutFileRoot     - Root name for any output files (use "" for .dvr rootname) (-)
True          TabDel          - When generating formatted output (OutForm=True), make output tab-delimited (fixed-width otherwise) (flag)
"ES15.6E3"    OutFmt          - Format used for text tabular output, excluding the time channel.  Resulting field should be 10 characters. (quoted string)
True          Beep            - Beep on exit (flag)
-----  Combined-Case Analysis  -------------------------------------------------
     200    NumCases        - Number of cases to run
WndSpeed       ShearExp       RotSpd        Pitch            Yaw           dT             Tmax
(m/s)            (-)          (rpm)         (deg)           (deg)          (s)            (s)
   8.0000000e+00   0.0000000e+00   2.2080000e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.2577085e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.3074171e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.3571256e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.4068342e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.4565427e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.5062513e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.5559598e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.6056683e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.6553769e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.7050854e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.7547940e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.8045025e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.8542111e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.9039196e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   2.9536281e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.0033367e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.0530452e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.1027538e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.1524623e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.2021709e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.2518794e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.3015879e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.3512965e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.4010050e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.4507136e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.5004221e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.5501307e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.5998392e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.6495477e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.6992563e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.7489648e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.7986734e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.8483819e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.8980905e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.9477990e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   3.9975075e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.0472161e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.0969246e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.1466332e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.1963417e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.2460503e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.2957588e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.3454673e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.3951759e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.4448844e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.4945930e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.5443015e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.5940101e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.6437186e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.6934271e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.7431357e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.7928442e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.8425528e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.8922613e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.9419698e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   4.9916784e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.0413869e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.0910955e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.1408040e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.1905126e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.2402211e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.2899296e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.3396382e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.3893467e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.4390553e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.4887638e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.5384724e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.5881809e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.6378894e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.6875980e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.7373065e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.7870151e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.8367236e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.8864322e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.9361407e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   5.9858492e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.0355578e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.0852663e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.1349749e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.1846834e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.2343920e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.2841005e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.3338090e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.3835176e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.4332261e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.4829347e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.5326432e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.5823518e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.6320603e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.6817688e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.7314774e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.7811859e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.8308945e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.8806030e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.9303116e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   6.9800201e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.0297286e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.0794372e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.1291457e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.1788543e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.2285628e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.2782714e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.3279799e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.3776884e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.4273970e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.4771055e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.5268141e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.5765226e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.6262312e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.6759397e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.7256482e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.7753568e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.8250653e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.8747739e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.9244824e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   7.9741910e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.0238995e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.0736080e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.1233166e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.1730251e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.2227337e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.2724422e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.3221508e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.3718593e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.4215678e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.4712764e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.5209849e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.5706935e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.6204020e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.6701106e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.7198191e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.7695276e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.8192362e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.8689447e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.9186533e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   8.9683618e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.0180704e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.0677789e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.1174874e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.1671960e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.2169045e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.2666131e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.3163216e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.3660302e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.4157387e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.4654472e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.5151558e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.5648643e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.6145729e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.6642814e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.7139899e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.7636985e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.8134070e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.8631156e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.9128241e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   9.9625327e+00   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0012241e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0061950e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0111658e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0161367e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0211075e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0260784e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0310492e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0360201e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0409910e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0459618e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0509327e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0559035e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0608744e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0658452e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0708161e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0757869e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0807578e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0857286e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0906995e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.0956704e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1006412e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1056121e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1105829e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1155538e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1205246e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1254955e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1304663e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1354372e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1404080e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1453789e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1503497e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1553206e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1602915e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1652623e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1702332e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1752040e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1801749e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1851457e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1901166e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.1950874e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.2000583e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.2050291e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01
   8.0000000e+00   0.0000000e+00   1.2100000e+01   0.0000000e+00   0.0000000e+00   1.3800000e-01   1.0000000e+01

Sorry for the inconvenience

Kindest regards

Younes

48

Dear Younes,

What aerodynamic modeling options have you selected in AeroDyn?

It could be, though, that AeroDyn has an implementation of BEM that is different from WT_Perf, so, I would not expect identical agreement.

I have not actually used the standalone AeroDyn driver to derived the Cp curve myself, but many years we did perform such an analysis in FAST with structural DOFs enabled. The response is also a bit different due to the influence of blade deflection.

Best regards,

49

Dear Jason,

Thank you for the reply. I changed the aerodynamic modeling to steady model AFAeroMod=1, and I got closer results. But I still have differences such as the maximum Cp is found at pitch -1° and TSR of 7.3 as you can see in the figures below.

Maybe I have the wrong parameters in my AeroDyn and AeroDyn_blade files. Here are they:
AeroDyn:

------- AERODYN v15.04.* INPUT FILE ------------------------------------------------
NREL 5.0 MW offshore baseline aerodynamic input properties.
======  General Options  ============================================================================
False         Echo               - Echo the input to "<rootname>.AD.ech"?  (flag)
"default"     DTAero             - Time interval for aerodynamic calculations {or "default"} (s)
          1   WakeMod            - Type of wake/induction model (switch) {0=none, 1=BEMT}
          1   AFAeroMod          - Type of blade airfoil aerodynamics model (switch) {1=steady model, 2=Beddoes-Leishman unsteady model} [must be 1 when linearizing]
          0   TwrPotent          - Type tower influence on wind based on potential flow around the tower (switch) {0=none, 1=baseline potential flow, 2=potential flow with Bak correction}
False         TwrShadow          – Calculate tower influence on wind based on downstream tower shadow? (flag)
True          TwrAero            - Calculate tower aerodynamic loads? (flag)
False         FrozenWake         - Assume frozen wake during linearization? (flag) [used only when WakeMod=1 and when linearizing]
False         CavitCheck         - Perform cavitation check? (flag) 
======  Environmental Conditions  ===================================================================
     1.225   AirDens            - Air density (kg/m^3)
 1.4639E-05   KinVisc            - Kinematic air viscosity (m^2/s)
        335   SpdSound           - Speed of sound (m/s)
     103500   Patm               - Atmospheric pressure (Pa) [used only when CavitCheck=True]
       1700   Pvap               - Vapour pressure of fluid (Pa) [used only when CavitCheck=True]
        0.1   FluidDepth         - Water depth above mid-hub height (m) [used only when CavitCheck=True]
======  Blade-Element/Momentum Theory Options  ====================================================== [used only when WakeMod=1]
          1   SkewMod            - Type of skewed-wake correction model (switch) {1=uncoupled, 2=Pitt/Peters, 3=coupled} [used only when WakeMod=1]
True          TipLoss            - Use the Prandtl tip-loss model? (flag) [used only when WakeMod=1]
true          HubLoss            - Use the Prandtl hub-loss model? (flag) [used only when WakeMod=1]
true          TanInd             - Include tangential induction in BEMT calculations? (flag) [used only when WakeMod=1]
False         AIDrag             - Include the drag term in the axial-induction calculation? (flag) [used only when WakeMod=1]
False         TIDrag             - Include the drag term in the tangential-induction calculation? (flag) [used only when WakeMod=1 and TanInd=TRUE]
      5E-05   IndToler           - Convergence tolerance for BEMT nonlinear solve residual equation {or "default"} (-) [used only when WakeMod=1]
      10000   MaxIter            - Maximum number of iteration steps (-) [used only when WakeMod=1]
======  Beddoes-Leishman Unsteady Airfoil Aerodynamics Options  ===================================== [used only when AFAeroMod=2]
          3   UAMod              - Unsteady Aero Model Switch (switch) {1=Baseline model (Original), 2=Gonzalez’s variant (changes in Cn,Cc,Cm), 3=Minemma/Pierce variant (changes in Cc and Cm)} [used only when AFAeroMod=2]
True          FLookup            - Flag to indicate whether a lookup for f' will be calculated (TRUE) or whether best-fit exponential equations will be used (FALSE); if FALSE S1-S4 must be provided in airfoil input files (flag) [used only when AFAeroMod=2]
======  Airfoil Information =========================================================================
          1   InCol_Alfa         - The column in the airfoil tables that contains the angle of attack (-)
          2   InCol_Cl           - The column in the airfoil tables that contains the lift coefficient (-)
          3   InCol_Cd           - The column in the airfoil tables that contains the drag coefficient (-)
          4   InCol_Cm           - The column in the airfoil tables that contains the pitching-moment coefficient; use zero if there is no Cm column (-)
          0   InCol_Cpmin        - The column in the airfoil tables that contains the Cpmin coefficient; use zero if there is no Cpmin column (-)
          8   NumAFfiles         - Number of airfoil files used (-)
"Airfoils\NREL_5MW\Cylinder1_10Hz.dat"    AFNames            - Airfoil file names (NumAFfiles lines) (quoted strings)
"Airfoils\NREL_5MW\Cylinder2_10Hz.dat"
"Airfoils\NREL_5MW\DU40_A17_10Hz.dat"
"Airfoils\NREL_5MW\DU35_A17_10Hz.dat"
"Airfoils\NREL_5MW\DU30_A17_10Hz.dat"
"Airfoils\NREL_5MW\DU25_A17_10Hz.dat"
"Airfoils\NREL_5MW\DU21_A17_10Hz.dat"
"Airfoils\NREL_5MW\NACA64_A17_10Hz.dat"
======  Rotor/Blade Properties  =====================================================================
True          UseBlCm            - Include aerodynamic pitching moment in calculations?  (flag)
"NRELOffshrBsline5MW_AeroDyn_blade.dat"    ADBlFile(1)        - Name of file containing distributed aerodynamic properties for Blade #1 (-)
"NRELOffshrBsline5MW_AeroDyn_blade.dat"    ADBlFile(2)        - Name of file containing distributed aerodynamic properties for Blade #2 (-) [unused if NumBl < 2]
"NRELOffshrBsline5MW_AeroDyn_blade.dat"    ADBlFile(3)        - Name of file containing distributed aerodynamic properties for Blade #3 (-) [unused if NumBl < 3]
======  Tower Influence and Aerodynamics ============================================================= [used only when TwrPotent/=0, TwrShadow=True, or TwrAero=True]
         12   NumTwrNds         - Number of tower nodes used in the analysis  (-) [used only when TwrPotent/=0, TwrShadow=True, or TwrAero=True]
TwrElev        TwrDiam        TwrCd
(m)              (m)           (-)
0.0000000E+00  6.0000000E+00  1.0000000E+00  
8.5261000E+00  5.7870000E+00  1.0000000E+00  
1.7053000E+01  5.5740000E+00  1.0000000E+00  
2.5579000E+01  5.3610000E+00  1.0000000E+00  
3.4105000E+01  5.1480000E+00  1.0000000E+00  
4.2633000E+01  4.9350000E+00  1.0000000E+00  
5.1158000E+01  4.7220000E+00  1.0000000E+00  
5.9685000E+01  4.5090000E+00  1.0000000E+00  
6.8211000E+01  4.2960000E+00  1.0000000E+00  
7.6738000E+01  4.0830000E+00  1.0000000E+00  
8.5268000E+01  3.8700000E+00  1.0000000E+00  
8.7600000E+01  3.8700000E+00  1.0000000E+00  
======  Outputs  ====================================================================================
False         SumPrint            - Generate a summary file listing input options and interpolated properties to "<rootname>.AD.sum"?  (flag)
          5   NBlOuts             - Number of blade node outputs [0 - 9] (-)
          4,          5,          6,          8,          9    BlOutNd             - Blade nodes whose values will be output  (-)
          0   NTwOuts             - Number of tower node outputs [0 - 9]  (-)
          1,          2,          3,          4,          5    TwOutNd             - Tower nodes whose values will be output  (-)
                   OutList             - The next line(s) contains a list of output parameters.  See OutListParameters.xlsx for a listing of available output channels, (-)
"RtAeroCp"  
"RtSpeed"
"RtTSR"
"RtVAvgxh"
END of input file (the word "END" must appear in the first 3 columns of this last OutList line)
---------------------------------------------------------------------------------------

AeroDyn_blade:

------- AERODYN v15.00.* BLADE DEFINITION INPUT FILE -------------------------------------
NREL 5.0 MW offshore baseline aerodynamic blade input properties
======  Blade Properties =================================================================
         18   NumBlNds           - Number of blade nodes used in the analysis (-)
  BlSpn        BlCrvAC        BlSwpAC        BlCrvAng       BlTwist        BlChord          BlAFID
   (m)           (m)            (m)            (deg)         (deg)           (m)              (-)
0.0000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.3308000E+01  3.5420000E+00          1 
2.8667000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.3308000E+01  3.5420000E+00          1      
5.6000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.3308000E+01  3.8540000E+00          1      
8.3333333E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.3308000E+01  4.1670000E+00          2      
1.1750000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.3308000E+01  4.5570000E+00          3      
1.5850000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.1480000E+01  4.6520000E+00          4      
1.9950000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.0162000E+01  4.4580000E+00          4      
2.4050000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  9.0110000E+00  4.2490000E+00          5      
2.8150000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  7.7950000E+00  4.0070000E+00          6      
3.2250000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  6.5440000E+00  3.7480000E+00          6      
3.6350000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  5.3610000E+00  3.5020000E+00          7      
4.0450000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  4.1880000E+00  3.2560000E+00          7      
4.4550000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  3.1250000E+00  3.0100000E+00          8      
4.8650000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  2.3190000E+00  2.7640000E+00          8      
5.2750000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.5260000E+00  2.5180000E+00          8      
5.6166700E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  8.6300000E-01  2.3130000E+00          8      
5.8900000E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  3.7000000E-01  2.0860000E+00          8      
6.1633333E+01  0.0000000E+00  0.0000000E+00  0.0000000E+00  1.0600000E-01  1.4190000E+00          8

Kindest regards

Younes
pitch1.PNG
pitch0.PNG

50

Dear Jason,

By changing the nodes in the AeroDyn_blade by the one given in Test01 of the AeroDyn files and running it at AFAeroMod=1, I got the Cp at the right pitch angle and TSR as shown below.

AeroDyn_blade for 5MW NREL:

[code]------- AERODYN v15.00.* BLADE DEFINITION INPUT FILE -------------------------------------
NREL 5.0 MW offshore baseline aerodynamic blade input properties
====== Blade Properties =================================================================
19 NumBlNds - Number of blade nodes used in the analysis (-)
BlSpn BlCrvAC BlSwpAC BlCrvAng BlTwist BlChord BlAFID
(m) (m) (m) (deg) (deg) (m) (-)
0.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.3308000E+01 3.5420000E+00 1
1.3666500E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.3308000E+01 3.5420000E+00 1
4.0999500E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.3308000E+01 3.8540000E+00 1
6.8332500E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.3308000E+01 4.1670000E+00 2
1.0249950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.3308000E+01 4.5570000E+00 3
1.4349950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.1480000E+01 4.6520000E+00 4
1.8449950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.0162000E+01 4.4580000E+00 4
2.2549950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 9.0110000E+00 4.2490000E+00 5
2.6649950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 7.7950000E+00 4.0070000E+00 6
3.0749950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 6.5440000E+00 3.7480000E+00 6
3.4849950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 5.3610000E+00 3.5020000E+00 7
3.8949950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 4.1880000E+00 3.2560000E+00 7
4.3049950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 3.1250000E+00 3.0100000E+00 8
4.7149950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 2.3190000E+00 2.7640000E+00 8
5.1249950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.5260000E+00 2.5180000E+00 8
5.4666650E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 8.6300000E-01 2.3130000E+00 8
5.7399950E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 3.7000000E-01 2.0860000E+00 8
6.0133250E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.0600000E-01 1.4190000E+00 8
6.1499900E+01 0.0000000E+00 0.0000000E+00 0.0000000E+00 1.0600000E-01 1.4190000E+00 8

[/code]

Thank you so much for the help and the guidance!

Kindest regards

Younes

CPAeroDyn.PNG
CPAeroDyn.PNG1604×873 121 KB

51

Dear Younes,

I’m glad you now get the result you were expecting.

Best regards,

52

Dear Jason Jonkman,

My question is indirectly related to FAST, and I would appreciate an answer if possible.
I am currently using a floating wind farm model (FOWFSim-Dyn) that uses the characteritics of the NREL 5-MW Semi-Submersible. I am using this model to study the impact of turbine repositionning on wind farm power production. Here, I simulated a wind farm composed of three turbines aligned in the direction of the wind. Each turbine is equipped with a controller that adjusts the turbine control inputs in response to a setpoint of position and power. Additionally, the controller uses aerodynamic stall regulation (with only negative pitch angles) as this regulation generates more thrust required for repositioning.

During the simulation, each turbine have to maximize their power production (according to the power curve of the NREL-5MW) while going to the prescribed positions. Here are the evolution the Cp and Ct coefficients for an incident wind of 14 m/s (the repositionning task starts at 500 s, just ignore the values before that):

image
image1818×744 124 KB

The Cp and Ct coefficients were empirically obtained from a precedent study using simulations under FAST and are represented in the form of tables Ct(Lambda,TSR) and Cp(Lambda,TSR). My question is: do the Cp and Ct coefficients maintained by the turbines seem correct or physically possible here? In fact, I am questioning the accuracy of these simulations because I believe that the induction factor must exceed 0.5 to obtain certain values (at some points, Ct briefly exceed 1 for some simulations). Could it be possible that the tables are inaccurate or this situation is just possible in some cases?

Best regards
Timothé Jard

53

Dear @Timothe.Jard,

For the NREL 5-MW baseline wind turbine, I would consider:

  • valid Cp between 0-0.49, depending on the TSR and pitch
  • valid Ct between 0.05-1.8, depending on the TSR and pitch, although Ct higher than about 1.1 are off-design conditions.

Best regards

54

Dear Jason Jonkman,

Thank you for your response, at least it is reassuring that the values seems logical and are contained within these intervals. Furthermore, I was wondering if there is a way (perhaps iteratively) to determine the axial induction factor of each wind turbine based on these combinations of coefficients and other parameters (such as TSR and blade pitch angle)?

Best Regards,
Timothé

55

Dear @Timothe.Jard,

For low thrust conditions, you could certainly use the classic momentum region of BEM to estimate the rotor-averaged induction from the rotor-averaged thrust coefficient, i.e.:

Ct = 4*a(1-a) → a = 1/2*(1-SQRT(1-Ct))

At higher thrust you’d have to apply, e.g., Glauert correction.

Best regards,

56

Dear Jason Jonkman,

Thank you for your reply.

As all my mean thurst coefficients are less than 0.96 (meaning a<0.4), I can now assume that the BEM theory is valid here.

Best Regards,

Timothé Jard

57

Dear all,

I am trying to obtain data for Cp over a larger range of TSR and pitch angle as well. I want to use this data in a lookup table in Simulink.
I am new to using OpenFAST / AeroDyn and currently struggling to get the simulation running correctly for quite some time. Thank you very much so far for all this content in this forum. I tried to comprehend your contributions but nevertheless did not manage it unfortunately.

As far as I understood, it is sufficient to use the AeroDyn module included in OpenFAST by running the AeroDyn driver file.
My goal is to obtain the Cp values by varying the rotor speed and pitch angle in this driver file (in the ad_BAR_CombinedCases folder). Unfortunately, my results don’t seem to make any sense at all:

RotSpeed10_Pitch22
RotSpeed10_Pitch221120×840 32.6 KB

the files that I used are the following (I adjusted them to suit my needs). The rotor speed varies from 0 rpm to 20 rpm and the pitch angle from 0 deg to 40 deg with an increment of 2 in both cases.

AeroDyn driver file

----- AeroDyn Driver Input File ---------------------------------------------------------
BAR turbine driver input file, using basic input
----- Input Configuration ---------------------------------------------------------------
False           Echo         - Echo input parameters to "<rootname>.ech"?
        0       MHK          - MHK turbine type (switch) {0: not an MHK turbine, 1: fixed MHK turbine, 2: floating MHK turbine}
        3       AnalysisType - {1: multiple turbines, one simulation, 2: one turbine, one time-dependent simulation, 3: one turbine, combined cases}
       11.0     TMax         - Total run time [used only when AnalysisType/=3] (s)
        0.5     DT           - Simulation time step [used only when AnalysisType/=3] (s)
"./OpenFAST_BAR_00_AeroDyn.dat"        AeroFile - Name of the primary AeroDyn input file
----- Environmental Conditions ----------------------------------------------------------
 1.225000000000000e+00     FldDens      - Density of working fluid (kg/m^3)
 1.477551020408163e-05     KinVisc      - Kinematic viscosity of working fluid (m^2/s)
 3.350000000000000e+02     SpdSound     - Speed of sound in working fluid (m/s)
 1.035000000000000e+05     Patm         - Atmospheric pressure (Pa) [used only for an MHK turbine cavitation check]
 1.700000000000000e+03     Pvap         - Vapour pressure of working fluid (Pa) [used only for an MHK turbine cavitation check]
                     0     WtrDpth      - Water depth (m)
----- Inflow Data -----------------------------------------------------------------------
          0      CompInflow  - Compute inflow wind velocities (switch) {0=Steady Wind; 1=InflowWind}
"unused"         InflowFile  - Name of the InflowWind input file [used only when CompInflow=1]
        9.0      HWindSpeed  - Horizontal wind speed   [used only when CompInflow=0 and AnalysisType=1] (m/s)
        140      RefHt       - Reference height for horizontal wind speed [used only when CompInflow=0]  (m)
       0.10      PLExp       - Power law exponent   [used only when CompInflow=0 and AnalysisType=1]                        (-)
----- Turbine Data ----------------------------------------------------------------------
1               NumTurbines  - Number of turbines
----- Turbine(1) Geometry ---------------------------------------------------------------
        True    BasicHAWTFormat(1) - Flag to switch between basic or generic input format {True: next 7 lines are basic inputs, False: Base/Twr/Nac/Hub/Bld geometry and motion must follow}
       0,0,0    BaseOriginInit(1) - Coordinate of tower base in base coordinates (m)
           3    NumBlades(1)    - Number of blades (-)
          3.    HubRad(1)       - Hub radius (m)
      140.82513 HubHt(1)        - Hub height (m)
          -7    Overhang(1)     - Overhang (m)
          -6    ShftTilt(1)     - Shaft tilt (deg)
          -4    Precone(1)      - Blade precone (deg)
     3.09343    Twr2Shft(1)     - Vertical distance from the tower-top to the rotor shaft (m)
----- Turbine(1) Motion [used only when AnalysisType=1] ---------------------------------
0               BaseMotionType(1)      - Type of motion prescribed for this base {0: fixed, 1: Sinusoidal motion, 2: arbitrary motion} (flag)
1               DegreeOfFreedom(1)     - {1:xg, 2:yg, 3:zg, 4:theta_xg, 5:theta_yg, 6:theta_zg} [used only when BaseMotionType=1] (flag)
5.0             Amplitude(1)           - Amplitude of sinusoidal motion   [used only when BaseMotionType=1] (m or rad)
0.1             Frequency(1)           - Frequency of sinusoidal motion   [used only when BaseMotionType=1] (Hz)
""              BaseMotionFileName(1)  - Filename containing arbitrary base motion (19 columns: Time, x, y, z, theta_x, ..., alpha_z)  [used only when BaseMotionType=2]
0               NacYaw(1)              - Yaw angle (about z_t) of the nacelle (deg)
7               RotSpeed(1)            - Rotational speed of rotor in rotor coordinates (rpm)
1               BldPitch(1)            - Blade 1 pitch (deg)
----- Time-dependent Analysis [used only when AnalysisType=2, numTurbines=1] ------------
"unused"         TimeAnalysisFileName - Filename containing time series (6 column: Time, HWndSpeed, PLExp, RotSpd, Pitch, Yaw). 
----- Combined-Case Analysis [used only when AnalysisType=3, numTurbines=1] -------------
         231  NumCases     - Number of cases to run
HWndSpeed     PLExp     RotSpd       Pitch          Yaw     dT      Tmax  DOF  Amplitude Frequency
(m/s)        (-)          (rpm)        (deg)        (deg)   (s)     (s)    (-)  (m or rad) (Hz)
  8.0           0.0          0.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          0.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          2.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          4.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          6.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          8.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          10.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          12.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          14.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          16.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          18.0         40.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         0.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         2.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         4.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         6.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         8.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         10.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         12.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         14.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         16.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         18.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         20.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         22.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         24.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         26.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         28.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         30.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         32.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         34.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         36.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         38.0          0.0     0.1     10      0     0.0      0.0
  8.0           0.0          20.0         40.0          0.0     0.1     10      0     0.0      0.0
----- Output Settings -------------------------------------------------------------------
"ES15.8E2"       OutFmt      - Format used for text tabular output, excluding the time channel.  Resulting field should be 10 characters. (quoted string)
1                OutFileFmt  - Format for tabular (time-marching) output file (switch) {1: text file [<RootName>.out], 2: binary file [<RootName>.outb], 3: both}
0                WrVTK       - VTK visualization data output: (switch) {0=none; 1=init; 2=animation}
1                WrVTK_Type  - VTK visualization data type: (switch) {1=surfaces; 2=lines; 3=both}
2                VTKHubRad   - HubRadius for VTK visualization (m)
-1,-1,-1,2,2,2   VTKNacDim   - Nacelle Dimension for VTK visualization x0,y0,z0,Lx,Ly,Lz (m)

( I will do a second post for the Aerodyn Input File because of to many characters.)

I checked those files several times. Can you please tell me what I am missing so far? Maybe there are some obvious mistakes that I made here.

And further, if I managed to get reasonable results, should I use an average of all Cp values for every distinct setting of pitch angle and rotor speed or just the last few because of some decaying oscillation effects? I read that averaging preferably over the azimuth was suggested but I don’t know what is exactly meant by that.

Also, the calculation of the TSR which comes from running AeroDyn seems odd to me. Taking the figure I attached for example: With a wind speed of v=8m/s, a rotational speed of n=10rpm and a rotor radius of R=63m, I expect the TSR to be
lambda = (2*pi)/60 * n * R / v = 8.25
Contrary to lambda = 13.49 from the simulation results.

Your help is very much appreciated since I really don’t know what else to do.

Many thanks in advance and I am looking forward to your guidance.

Kind regards,

Hendrik

58

Dear all,

here is the AeroDyn Input File I mentioned in the original post:

AeroDyn Input File

------- AERODYN INPUT FILE --------------------------------------------------------------------------
Generated with AeroElasticSE FAST driver
======  General Options  ============================================================================
False                  Echo        - Echo the input to "<rootname>.AD.ech"? (flag)
"default"              DTAero      - Time interval for aerodynamic calculations {or "default"} (s)
1                      Wake_Mod    - Wake/induction model (switch) {0=none, 1=BEMT, 3=OLAF} [Wake_Mod cannot be 2 or 3 when linearizing]
0                      TwrPotent   - Type tower influence on wind based on potential flow around the tower (switch) {0=none, 1=baseline potential flow, 2=potential flow with Bak correction}
0                      TwrShadow   - Calculate tower influence on wind based on downstream tower shadow (switch) {0=none, 1=Powles model, 2=Eames model}
False                  TwrAero     - Calculate tower aerodynamic loads? (flag)
False                  CavitCheck  - Perform cavitation check? (flag) [UA_Mod must be 0 when CavitCheck=true]
False                  Buoyancy    - Include buoyancy effects? (flag)
False                  NacelleDrag - Include Nacelle Drag effects? (flag)
False                  CompAA      - Flag to compute AeroAcoustics calculation [used only when Wake_Mod = 1 or 2]
"AeroAcousticsInput.dat" AA_InputFile - AeroAcoustics input file [used only when CompAA=true]
======  Environmental Conditions  ===================================================================
"default"              AirDens     - Air density (kg/m^3)
"default"              KinVisc     - Kinematic viscosity of working fluid (m^2/s)
"default"              SpdSound    - Speed of sound in working fluid (m/s)
"default"              Patm        - Atmospheric pressure (Pa) [used only when CavitCheck=True]
"default"              Pvap        - Vapour pressure of working fluid (Pa) [used only when CavitCheck=True]
======  Blade-Element/Momentum Theory Options  ====================================================== [unused when Wake_Mod=0 or 3, except for BEM_Mod]
1                      BEM_Mod     - BEM model {1=legacy NoSweepPitchTwist, 2=polar} (switch) [used for all Wake_Mod to determine output coordinate system]
--- Skew correction
1                      Skew_Mod    - Skew model {0=No skew model, -1=Remove non-normal component for linearization, 1=skew model active}
False                  SkewMomCorr - Turn the skew momentum correction on or off [used only when Skew_Mod=1]
default                SkewRedistr_Mod - Type of skewed-wake correction model (switch) {0=no redistribution, 1=Glauert/Pitt/Peters, default=1} [used only when Skew_Mod=1]
"default"              SkewRedistrFactor - Constant used in Pitt/Peters skewed wake model {or "default" is 15/32*pi} (-) [used only when Skew_Mod=1 and SkewRedistr_Mod=1]
--- BEM algorithm 
True                   TipLoss     - Use the Prandtl tip-loss model? (flag) [unused when Wake_Mod=0 or 3]
True                   HubLoss     - Use the Prandtl hub-loss model? (flag) [unused when Wake_Mod=0 or 3]
True                   TanInd      - Include tangential induction in BEMT calculations? (flag) [unused when Wake_Mod=0 or 3]
True                   AIDrag      - Include the drag term in the axial-induction calculation? (flag) [unused when Wake_Mod=0 or 3]
True                   TIDrag      - Include the drag term in the tangential-induction calculation? (flag) [unused when Wake_Mod=0,3 or TanInd=FALSE]
"Default"              IndToler    - Convergence tolerance for BEMT nonlinear solve residual equation {or "default"} (-) [unused when Wake_Mod=0 or 3]
100                    MaxIter     - Maximum number of iteration steps (-) [unused when Wake_Mod=0]
--- Shear correction
False                  SectAvg     - Use sector averaging (flag)
1                      SectAvgWeighting - Weighting function for sector average {1=Uniform, default=1} within a sector centered on the blade (switch) [used only when SectAvg=True]
default                SectAvgNPoints - Number of points per sectors (-) {default=5} [used only when SectAvg=True]
default                SectAvgPsiBwd - Backward azimuth relative to blade where the sector starts (<=0) {default=-60} (deg) [used only when SectAvg=True]
default                SectAvgPsiFwd - Forward azimuth relative to blade where the sector ends (>=0) {default=60} (deg) [used only when SectAvg=True]
--- Dynamic wake/inflow
1                      DBEMT_Mod   - Type of dynamic BEMT (DBEMT) model {0=No Dynamic Wake, -1=Frozen Wake for linearization, 1:constant tau1, 2=time-dependent tau1, 3=constant tau1 with continuous formulation} (-)
20                     tau1_const  - Time constant for DBEMT (s) [used only when DBEMT_Mod=1 or 3]
======  OLAF -- cOnvecting LAgrangian Filaments (Free Vortex Wake) Theory Options  ================== [used only when Wake_Mod=3]
"OLAF.dat"             OLAFInputFileName - Input file for OLAF [used only when Wake_Mod=3]
======  Unsteady Airfoil Aerodynamics Options  ====================================================
False                  AoA34       - Sample the angle of attack (AoA) at the 3/4 chord or the AC point {default=True} [always used]
0                      UA_Mod      - Unsteady Aero Model Switch (switch) {0=Quasi-steady (no UA), 2=B-L Gonzalez, 3=B-L Minnema/Pierce, 4=B-L HGM 4-states, 5=B-L HGM+vortex 5 states, 6=Oye, 7=Boeing-Vertol}
True                   FLookup     - Flag to indicate whether a lookup for f' will be calculated (TRUE) or whether best-fit exponential equations will be used (FALSE); if FALSE S1-S4 must be provided in airfoil input files (flag) [used only when AFAeroMod=2]
3               IntegrationMethod  - Switch to indicate which integration method UA uses (1=RK4, 2=AB4, 3=ABM4, 4=BDF2)
0                      UAStartRad  - Starting radius for dynamic stall (fraction of rotor radius [0.0,1.0]) [used only when UA_Mod>0; if line is missing UAStartRad=0]
1                      UAEndRad    - Ending radius for dynamic stall (fraction of rotor radius [0.0,1.0]) [used only when UA_Mod>0; if line is missing UAEndRad=1]
======  Airfoil Information =========================================================================
1                      AFTabMod    - Interpolation method for multiple airfoil tables {1=1D interpolation on AoA (first table only); 2=2D interpolation on AoA and Re; 3=2D interpolation on AoA and UserProp} (-)
1                      InCol_Alfa  - The column in the airfoil tables that contains the angle of attack (-)
2                      InCol_Cl    - The column in the airfoil tables that contains the lift coefficient (-)
3                      InCol_Cd    - The column in the airfoil tables that contains the drag coefficient (-)
4                      InCol_Cm    - The column in the airfoil tables that contains the pitching-moment coefficient; use zero if there is no Cm column (-)
0                      InCol_Cpmin - The column in the airfoil tables that contains the Cpmin coefficient; use zero if there is no Cpmin column (-)
30                     NumAFfiles  - Number of airfoil files used (-)
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_00.dat" AFNames - Airfoil file names (NumAFfiles lines) (quoted strings)
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_01.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_02.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_03.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_04.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_05.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_06.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_07.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_08.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_09.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_10.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_11.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_12.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_13.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_14.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_15.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_16.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_17.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_18.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_19.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_20.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_21.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_22.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_23.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_24.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_25.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_26.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_27.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_28.dat"
"../BAR_Baseline/Airfoils/BAR0_AeroDyn_Polar_29.dat"
======  Rotor/Blade Properties  =====================================================================
True                   UseBlCm     - Include aerodynamic pitching moment in calculations? (flag)
"../BAR_Baseline/OpenFAST_BAR_00_AeroDyn_blade.dat" ADBlFile(1) - Name of file containing distributed aerodynamic properties for Blade #1 (-)
"../BAR_Baseline/OpenFAST_BAR_00_AeroDyn_blade.dat" ADBlFile(2) - Name of file containing distributed aerodynamic properties for Blade #2 (-) [unused if NumBl < 2]
"../BAR_Baseline/OpenFAST_BAR_00_AeroDyn_blade.dat" ADBlFile(3) - Name of file containing distributed aerodynamic properties for Blade #3 (-) [unused if NumBl < 3]
======  Hub Properties ============================================================================== [used only when Buoyancy=True]
0                      VolHub      - Hub volume (m^3)
0                      HubCenBx    - Hub center of buoyancy x direction offset (m)
======  Nacelle Properties ========================================================================== [used only when Buoyancy=True or NacelleDrag=True]
0                      VolNac      - Nacelle volume (m^3)
0.0, 0.0, 0.0   NacCenB            - Position of nacelle center of buoyancy from yaw bearing in nacelle coordinates (m)
0, 0, 0      NacArea        - Projected area of the nacelle in X, Y, Z in the nacelle coordinate system (m^2)
0, 0, 0   NacCd          - Drag coefficient for the nacelle areas defined above (-)
0, 0, 0         NacDragAC          - Position of aerodynamic center of nacelle drag in nacelle coordinates (m)
======  Tail Fin Aerodynamics =======================================================================
False                  TFinAero    - Calculate tail fin aerodynamics model (flag)
"unused"               TFinFile    - Input file for tail fin aerodynamics [used only when TFinAero=True]
======  Tower Influence and Aerodynamics ============================================================ [used only when TwrPotent/=0, TwrShadow/=0, TwrAero=True, or Buoyancy=True]
9                      NumTwrNds   - Number of tower nodes used in the analysis (-) [used only when TwrPotent/=0, TwrShadow/=0, TwrAero=True, or Buoyancy=True]
TwrElev        TwrDiam        TwrCd          TwrTI          TwrCb         ! TwrTI used only when TwrShadow=2; TwrCb used only when Buoyancy=True
(m)            (m)            (-)            (-)            (-)           
3.4300000E+01  8.5000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
4.1100000E+01  8.2000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
5.4800000E+01  7.6000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
6.8500000E+01  7.0000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
8.2200000E+01  6.4000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
9.5900000E+01  5.8000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
1.0960000E+02  5.2000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
1.2330000E+02  4.6000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
1.3700000E+02  4.0000000E+00  1.0000000E+00  1.0000000E-01  0.0000000E+00
======  Outputs  ====================================================================================
False                  SumPrint    - Generate a summary file listing input options and interpolated properties to "<rootname>.AD.sum"? (flag)
0                      NBlOuts     - Number of blade node outputs [0 - 9] (-)
1, 4, 7, 13, 18, 23, 26, 28, 30 BlOutNd     - Blade nodes whose values will be output (-)
0                      NTwOuts     - Number of tower node outputs [0 - 9] (-)
1, 2, 6                TwOutNd     - Tower nodes whose values will be output (-)
                       OutList     - The next line(s) contains a list of output parameters.  See OutListParameters.xlsx for a listing of available output channels, (-)
"RtAeroCp"                 - Cp
"RtAeroCq"                 - Cq
"RtAeroCt"                 - Ct                 
"RtSpeed"                  - RtSpeed
"RtTSR"                    - TSR
END of OutList section (the word "END" must appear in the first 3 columns of the last OutList line)
---------------------- NODE OUTPUTS --------------------------------------------
0                      BldNd_BladesOut  - Number of blades to output all node information at.  Up to number of blades on turbine. (-)
ALL                    BldNd_BlOutNd   - Specify a portion of the nodes to output. {"ALL", "Tip", "Root", or a list of node numbers} (-)
                       OutList_Nodal - The next line(s) contains a list of output parameters.  See OutListParameters.xlsx for a listing of available output channels, (-)
"Fx"                       
"Vx"                       
"VUndx"                    
"Vrel"                     
"AxInd"                    
"Vindx"                    
END (the word "END" must appear in the first 3 columns of this last OutList line in the optional nodal output section)
====================================================================================================

Again, I am really looking forward to your help.

Kind regards,

Hendrik

59

Dear Younes,

thank you very much for your contribution. Is it possible that you provide the data of the figure with the correct results for Cp that you have shown?
This would help me so much since I am struggling to get reasonable results as I mentioned in my other post.

I am still interested in getting the simulation running correctly but this would make me not that much dependent on this anymore.

Many thanks in advance.

Kind regards,

Hendrik

60

Dear @Hendrik.Groeger,

Just a few comments:

  • Are you trying to compute the steady-state performance of the NREL 5-MW baseline wind turbine or the BAR turbine? The input files you are using are for the BAR turbine.
  • For TSR, you mention R = 63 m, but the BAR turbine has a blade length of 100 m, for R = 103 m, which matches the TSR reported by AeroDyn.
  • I see that your AeroDyn file has dynamic wake enabled (DBEMT_Mod = 1), which I’m not sure is what you want for computing steady-state performance. I suggest setting DBEMT_Mod = 0.
  • When computing a steady-state solution, I’d recommend ensuring that the solution has converged and then eliminate any remaining periodicity by azimuth averaging, i.e., averaging the solution across one (or more) full rotations of the rotor.

Best regards,