Hi all,
I have been looking at the source codes for the AeroDyn_v15 module to find where AeroDyn forces the induction to go to 1 at the tip and the hub. Can someone please help me find where in the source code this calculation happens? I will be very grateful for your help.
Thanks in advance and best regards,
Vishal
Vishal,
In subroutine BEMTU_InductionWithResidual(), the condition if ( p%FixedInductions(i,j) ) is where it sets the axial induction to 1 at the tip/hub when the tiploss/hubloss models are used.
Hi All,
I would like to use CFD based tip loss model as mentioned in the Aerodyn tutorial like Xu&Sarkar. I understand that this is rotor specific. I have now load variation from CFD and want to apply the function that I have instead of Prandtl’s. Could you please let me know where is Xu&Sarkar et.al in the Aerodyne source code and how can I use that in the Aerodyn input file for the OpenFAST simulation e.g. 5MW or 15MW example blade?
Best regards
Ramesh
Dear @Ramesh.Kumar,
AeroDyn v14 and earlier supported multiple tip loss models, but this functionality was not included in AeroDyn v15 within OpenFAST, which only supports the Prandtl tip and hub loss models. AeroDyn v14 is currently supported by OpenFAST, but will be deprecated very soon, so, is not worth changing. I would suggest adding the option to AeroDyn v15. The Prandtl tip and hub loss correction is implemented in AeroDyn v15 within FUNCTION getHubTipLossCorrection() in source file BEMTUncoupled.f90.
Best regards,
Dear Jason,
Thanks for replying. I will try to add into AeroDyn v15. However, In order to run the AeroDyn V14 Tip loss model should I only define the aerodyne input file in v14 format?
My next question is on load calculation. For IEA 15MW, I have run the power production and parked load case (only high wind not the yaw error) the resulting bending moment are well within the design load envelope. The rotor thrust is higherst at the rated. I wonder which load case results in highest bending load on blade section. Is it reported somewhere to refer? and what is corresponding rotor thrust? and how thrust look as compared to rated thrust?
Best regards
Ramesh
Dear @Ramesh.Kumar,
Yes, to run AeroDyn v14 within OpenFAST requires the use of an AeroDyn input file formatted for v14.
I’m not an expert on the loads analysis of the IEA Wind 15-MW reference wind turbine, but I would suggest reviewing the loads analysis section of its specifications report for more information: https://www.nrel.gov/docs/fy20osti/75698.pdf.
Best regards,
Dear @Jason.Jonkman
Thank you very much for replyinh, According to this report DLC 1.4 and DLC 1.5 are governing load cases for flapwise root bending moment. I will try to run above load cases first. I am interested to see how the rotor thrust for these load cases are lower than the rated? If anyone has the thrust number for these load cases would be great. I am keen to understand on any platform (if you have for 5MW, 10MW etc) , how the resulting forces translated to the tower top? how the thrust for DLC 1.4 & DLC1.5 are in comparison to the rated DLC1.1?
Best regards
Ramesh
Dear @Ramesh.Kumar,
I performed the loads analysis for the NREL 5-MW baseline wind turbine. You can find the extreme event tables (including rotor thrust and tower-top loads) for the land-based version of the NREL 5-MW baselien wind turbine in Appendix F.1 of my PhD thesis-turned NREL report: https://www.nrel.gov/docs/fy08osti/41958.pdf.
You’ll have to ask the authors of the IEA Wind 15-MW specifications report if similar extreme event tables are available from the loads analysis that has been performed.
Best regards,
Dear @Jason.Jonkman
Thank you very much. 5MW report is really helpful.
@Evan.Gaertner @Jennifer.Rinker @Latha.Sethuraman Could you please help me on IEA 15MW Rotor thrust, aerodynamic load + inertia contribution breakdown for DLC 1.4/1.5 (max root flap bending moment DLCs’)?
Best regards
Ramesh
Dear @Jason.Jonkman
I managed to run DLC 1.4 and rotor thrust in this DLC is (max is 3.91MN instead of rated ~2.8MN) and look more sensible. However, I get few spikes of noise in two of three simulations. What is your thought?
Best regards
Ramesh
Dear @Ramesh.Kumar,
If you ever see “spikes” in simulation results, it is best to identify their cause to understand if they are physical or not. Do they arise from tower shadow, control, unsteady airfoil aerodynamics, etc.? This could be identified by toggling features on/off.
Best regards,
Dear @Jason.Jonkman
Thanks for your quick responses and suggestions. I will debug the issue.
Best regards
Ramesh
