[Armitage]

Hi all,

I am trying to analyse the ability of a standard of the shelf self-bailer for passively reducing hull drag by introducing an air layer below the hull for a range of velocities.

I have made a 2D model that is churning out what seem to me to be sensible Cd's of around 0.85 for 5 m/s of flow.

However when performing 3D analysis I am getting a Cd of between 0.02 and 0.03 for 5 m/s. This seems far too low to me, or is it a vague possibility?

I have refined my 3D mesh quite a lot, using inflation in the boundary layer and I have run out of ideas. If anyone could give me any thoughts or point me in the direction of some useful validation resource, that would be very helpful.

Thank you!