Vent placement on stepped hull.

[Ad Hoc]

.....Since the flow losses along the aft buttocks and the transom venting depend on different flow mechanisms, the combined loss from the two must be speed dependant, ie the optimum transom/hull depth ratio will vary with design speed.

Yup that's what we found with our fast ferry designs and tank testing to get the "sweet spot" over a nominal range.

 

[Bob Rosa]

Sorry for being lost on this for a few days. Honey Due list and pressure got to long. two new photos to look at.