This video shows further progress on the buoyancy system. The main change is the sphere-foil model used to calculate the forces acting on the pontoons.
The first part of the video shows the watercraft with spherical pontoons for which buoyant force and drag force are calculated (the same watercraft as in the previous video). The drag coefficient of spherical pontoons does not depend on the direction of their velocities relative to the flow. In contrast, the drag coefficient of sphere-foil pontoons may depend on the velocity direction relative to the flow. In addition, the lift force is also calculated. All this together allows the sphere-foil model to be used to simulate hydrofoil crafts, which is demonstrated in the second part of this video.
Of greatest interest in this context are the following values, displayed in the HUD in the lower right corner of the screen:
orbital_speed, that is, the speed relative to the ground;
thrust_max in m/s2, which should be multiplied by the mass of the watercraft (which is about 500 kg) to obtain the thrust in Newtons;