John Winters wrote: > >Poly boats do have more resistance due to the surface finish (rough center >seams etc..) and propensity of scratches that are proud of the hull >surface and often have hairy projections. The increase in frictional >resistance coefficient is roughly 3%. Not a whole lot but there >nonetheless. Brian Heath replied: >Thus, in terms of energy spent in a long day of paddling, it >sounds like 3% or so is my only worry. And that is well within my range of >acceptable. Thanks! I don't know about boat hulls, but with airplane wings, a rough surface, such as clear and especially rime icing not only increases the coeficient of resistance (called drag) it completeley destroys the lift capacity of the wing. A little roughness on the surface destroys the laminar flow... In other words... it won't fly. I would suspect that a boat hull might be similarly, although not as drastically, effected. I mean, it is not going to sing. However, it is not the resistance that is so critical with the wing, but the destruction of laminar flow. The question is John, does this analogy apply to the boat hull and is the 3% therefore, worse than it sounds? Robert *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************Received on Tue May 26 1998 - 18:22:02 PDT
This archive was generated by hypermail 2.4.0 : Thu Aug 21 2025 - 16:29:57 PDT