hello

When I set the range of waves to 0 degrees and the direction of the current to 0 degrees, why is the shear force on my fixed foundation still positive or negative?

There is also the question when I turn off six degrees of freedom in Elastodyn, why doesn’t the buoyancy force of the fixed base change with the wave height?

Dear @Zhao.Dang,

Can you clarify what OpenFAST model are you simulating? Is this one of the OpenFAST models from the r-test (GitHub - OpenFAST/r-test) or your own OpenFAST model?

Does the simulation you are running have aerodynamic loads enabled, or just excitation from waves and current.

Best regards,

Thanks for your reply

I don’t turn on aerodynamics, there are only waves and currents, and they are in the same direction. From this IEA-15-240-RWT-Monopile

When there is only wave flow load and in the same direction, there are positive and negative peaks of the horizontal wave flow load on the foundation.

Closing six degrees of freedom in ELastodyn, quite fixed with both ends, why the buoyancy force of the base does not change with the change of wave height

Dear @Zhao.Dang,

I’m not sure I fully understand your question(s).

If you disable the platform degrees of freedom (DOFs) of ElastoDyn, then the loads from the wind turbine (including weight) will not be transferred to the SubDyn model, and the Guyan modes of the SubDyn model will be disabled. I would only disable the platform DOFs of ElastoDyn when coupled to SubDyn for debugging purposes.

Hydrostatic pressure does not create a buoyancy force on a monopile embedded into the seabed because pressure only applies normal to the surface of a body, and there are no surfaces on an embedded monopile whose normal vector is directed vertically.

Best regards,