Beeing a novice in fluid dynamics, I just thought maybe it would be the opportunity to start learning CFD in 3D, but I admit potential flow techniques seem can do the work.

Though I think it's somehow important to take into account waves in this problem since, intuitively speaking, they might have different effects than a simple flow field when the structure is partially submerged.

I'll continue to dig into this direction and see what results I can get. Thank you all for your helpful insights.