Abstract
The oar blade acts as hydrofoil in stroke phase. Its angle of attack and velocity of incoming flow is not constant but transient so that the load which acts on the oar blade should be unsteady. It is absolutely necessary to estimate the load to analyze the rowing motion. But it is not appropriate to estimate with assuming steady state.
We carried a tank test using a circulating water channel. A flat plate attached to a load cell rotated in uniform flow and angle of attack varied according to the rotation of the plate. The result of this experiment indicates that the unsteady load is much larger than the steady one. And the load was properly arranged by reduced frequency. A method to estimate the unsteady load from the angle of attack and the velocity of incoming flow was established.
