I am trying to run a multiphase simulation to get resistance forces for a small trimaran boat (24 ft long by 8 ft wide overall).
I have tried to copy the approach used by dheiny ( SimScale in terms of domain setup, boundary conditions, etc.
The problem is this - for a boat of this size I would expect resistance numbers on the order of 400 to 1000 pounds at 20 knots. The results from Simscale are a good two orders of magnitude higher, in the 10’s and 100’s of thousands of pounds or more. Somehow, despite specifying inlet and outlet velocities of 20 knots / 10 m/s, the program is generating much higher velocities. Can somebody tell me why this might be?
So far I have tried switching to metric units, adjusting the mesh size, reducing the time step, and changing to laminar flow.