SOWFA - tutorial fastDuct - Wind Speed

Wind & Water Computer-Aided Engineering Software Tools
1

Hello!

I am a physics student trying to get familiar with the SOWFA program.

When I run the tutorial fastDuct with the given FAST output parameters it works fine, but for comparison with other simulations I want to set them as follows in the file primary.fst:

"WindVxi , WindVyi , WindVzi" "GenPwr , GenTq" "RotThrust, RotTorq" "RotCq, RotCp, RotCt" "BldPitch1" "Azimuth , YawPos" "RotSpeed , GenSpeed , TSR" "TTDspFA , TTDspSS , TTDspTwst" "Spn2MLxb1, Spn2MLyb1" "RootFxc1 , RootFyc1 , RootFzc1" "RootMxc1 , RootMyc1 , RootMzc1" "RotTorq , LSSGagMya, LSSGagMza" "YawBrFxp , YawBrFyp , YawBrFzp" "YawBrMxp , YawBrMyp , YawBrMzp" "TwrBsFxt , TwrBsFyt , TwrBsFzt" "TwrBsMxt , TwrBsMyt , TwrBsMzt"
The wind velocity vector in the file fastDuct/0/U is set to uniform (8.0 0 0) and I expect the value ‘WindVxi’ to be 8.0 accordingly.
This is not the case! Although in ParaView I get the right wind speed, the FAST output file primary0.out always gives:

WindVxi WindVyi WindVzi 1.000E+01 0.000E+00 0.000E+00
no matter which input parameter I set!

Do I need to change another input file in order to get correct output results or is the wind velocity just not transferred to primary0.out?

Thanks in advance for your help!

Darja

2

The hub height wind speed is something we need to work on. The wind velocity at the hub passing from CFD to FAST is currently disconnected. The future version will have this capability.

3

Thanks for your quick response.
I now have another question concerning the air density.

I would like to simulate the fastDuct tutorial case with different air densities. In the file NRELOffshrBsline5MW_AeroDyn.ipt there is a value for air density set to

1.225    AirDens     - Air density (kg/m^3)

Is this handed over to OpenFOAM for the distribution of forces or is it neccessary to adjust the value in another file accordingly?

Thanks in advance!

Darja