scrambledegg
Member
My boat is in a yard about to have all its skin fittings and seacocks replaced. It currently has flush fittings and I could replace like with like, but it is cheaper to replace with the slightly protruding type with external flange. There's going to be increased drag with these protruding types and I am reluctant to go that route but the economics can't be ignored.
Does anyone have hard data about that drag increase?
My limited understanding is that such a skin fitting on a part of the hull that has laminar flow could increase drag considerably , as it would cause the flow to transition from laminar to turbulent. On a part of the hull that is normally turbulent perhaps it would have very little effect on the drag? Unless, that is, it provokes flow separation. Where on typical hulls is the flow laminar and turbulent?
As you can tell I am guessing quite a bit. Is there anybody out there who's studied this, or knows of a study and would be prepared to share?
Yours hopefully.
Does anyone have hard data about that drag increase?
My limited understanding is that such a skin fitting on a part of the hull that has laminar flow could increase drag considerably , as it would cause the flow to transition from laminar to turbulent. On a part of the hull that is normally turbulent perhaps it would have very little effect on the drag? Unless, that is, it provokes flow separation. Where on typical hulls is the flow laminar and turbulent?
As you can tell I am guessing quite a bit. Is there anybody out there who's studied this, or knows of a study and would be prepared to share?
Yours hopefully.