Hello fellow engineers,
The problem with oscillating forces might have something to do with the geometry being bad. Here are a few snapshots showing the old geometry with selection of external and internal faces:
As one can see, there exist surface intersections between external and internal surfaces. I chose a simpler geometry that I closed from the top. Now, the geometry is free from surface intersections:
With this geometry, I re-ran the simulation. Now the forces converge to a constant value. Water flows in the -z direction.
Here are the forces in the important directions, i.e., x, and z directions:
Please note that the actual values of these forces might not be accurate, since on the platform only 1 reference density is used for computing forces on the selected surfaces.
The Kelvin Wake remains the same: