[jesdreamer]

The Box Cavity photo shows what I referred to as a recessed back KammBack configuration. And I realize that Renold's Number is involved -- but it has been many many years since my college fluid dynamics course and I need some help in learning whether a recessed KammBack would help reduce drag in a fluid denser than air (such as water) -- I am considering airfoil (hydrofoil) structures and plan to truncate as per the info posted above but would like to explore some calculations and am lost in the math. I don't have a clue as to how to mathematically treat or explore effect on drag (if any) as related to the recess distance back behind the outer projecting edge -- For that matter,
will the drag reduction of truncating downstream end of an airfoil (hydrofoil) in water have proportionally a similar effect as per info above for air as the fluid??