SOWFA Support

Wind & Water Computer-Aided Engineering Software Tools
61

Another thing you could do with the precursor is to rotate the domain so that the wind isn’t exactly normal to the periodic boundary. This would effectively increase the simulated streamwise extent and help break up larger structures. Overall, assuming you’re averaging over a 10-min window, these results are consistent with what I’ve seen in my work as well.

62

I see. Thank you for your advice.

63

I am carrying out a project in which we are trying to numerically simulate wakes behind land based turbines using LES.

We are testing SOWFA-6-dev from github, and we re-purposed the NREL15MW tutorial files to the specifications for NREL5MW. We tried to simulate flow around a single turbine with actuator disk model (10 m grid size) in which the inflow was uniform 8 m/s.

The power output is only around 1 MW, which is almost half of what we would expect at this wind speed (i.e. around 2MW). Reducing the grid cell width, increasing epsilon, or changing the generator options did not change this result much.

A summary of the OpenFAST settings are:
https://www.dropbox.com/s/db51cxbgfroqq8l/SOWFA_query.pdf?dl=0

Relevant OpenFAST and SOWFA input files can be found here:
https://www.dropbox.com/s/7de4lwbsi8ai9m2/test_NREL_5MW_land_uniform_in_simple_VS_pitch_0.zip?dl=0

Any help on this issue will be great.

64

Hello all,

I’m running a precursor simulation very similar to the neutral ABL example case and I’m having a problem with the boundary data sampling. I’ve used many different settings for the function object “boundaryDataPre” (including of course the baseline one from github https://github.com/NREL/SOWFA/blob/master/exampleCases/example.ABL.flatTerrain.neutral/system/sampling/boundaryDataPre). However, the result is always the same: folders are created for each timestep but they are always empty. This leaves me with a few questions:

  • Does the simulation have to finish before I can see the data in the postProcessing folder?
  • Is the problem related to my cluster’s capability to read/write data?

At this point I have no clue what is going on and I’ve run out of ideas, so I’d really appreciate any help. Has anyone encountered a similar problem?

Thanks for your time,
Juan

The setting I’m using now is the following:

Blockquote
boundaryDataPre
{
type surfaces;
functionObjectLibs (“libsampling.so”);
enabled true;
interpolationScheme isThisNeeded;
outputControl timeStep;
outputInterval 1;
surfaceFormat foamFile;
fields
(
U
T
k
);
surfaces
(
west
{
type patch;
patches (west);
triangulate false;
}
);
}

65

Please set the switch WakeMod=0 in aerodyn file.
You will get the correct power output.

66

Hello,

I have been moving SOWFA over from the earlier form of open foam to a new one so that we can use it with the other developed codes we have here in our group. It has all seemed to work and compiled with no adjustments. However when I come to run it using the ABLSolver, as it is creating the fields it always fails when it gets to Creating divergence scheme blending factor field, UBlendingFactor.

Claiming it cannot find it in the run folder (e.g example.ABL.flatTerrain.neutral/processor0/0/UBlendingFactor). However as far as i understand the code it should be creating said file not looking for it. I am not sure why this happens especially as the solver compiles fine. I am admittedly also using the other type of OpenFOAM. has anyone come across this problem before and has a solution?

67

essentially it is giving up here
// Create the blending factor fields.
Info << “Creating divergence scheme blending factor field, UBlendingFactor…” << endl;
surfaceScalarField UBlendingFactor
(
IOobject
(
“UBlendingFactor”,
runTime.timeName(),
mesh,
IOobject::READ_IF_PRESENT,
IOobject::AUTO_WRITE
),
mesh,
1.0
);

Info << "Creating divergence scheme blending factor field, TBlendingFactor..." << endl;
surfaceScalarField TBlendingFactor
(
    IOobject
    (
        "TBlendingFactor",
        runTime.timeName(),
        mesh,
        IOobject::READ_IF_PRESENT,
        IOobject::AUTO_WRITE
    ),
    mesh,
    1.0
);
68

Hi Amitabh Bhattacharya,

I hope you are well.

I am a student looking to use SOWFA-6 to simulate wakes behind offshore wind turbines. Although successful with the precursor stages, I am having some issues with running the software to incorporate wind turbines.

I just had a couple of questions, firstly I’m wondering if you managed to successfully run this SOWFA case successfully? Also, I have looked at your input files, but cannot see any preprocess or solve scripts, would the basic tutorial scrips suffice or have you made your own ones?

I appreciate communicating on this forum may not be the best for you so, if easier, my university email is ptjh72@durham.ac.uk.

Many thanks,
Patrick

70

Hi All,

Could you please let me know the latest version compatibility between OpenFOAM and OpenFAST?

  • I have Openfoam-11 installed and working for CFD
  • I also have OpenFAST installed and working
  • I am using these on Ubuntu 22.04.1 LTS.

Many thanks!

Best regards