But to get the sail-wind interaction you need the movement of the boat. To get the movement you then need the hull-water interaction. Modeling just a static, vertical, sail doesnt really demonstrate anything practical. It is more akin to similating a captive foil in a wind tunnel.

The obvious next step would be to calculate the cog and tilt the entire rig in response to sail forces, which sheds wind until a balance point is reached, or the boat flips.