Numerical Experiment of Flow around a Flat Plate with Round Edges

A numerical experiment around a flat plate with round edges (round flat plate) was performed using the vortex method. The round flat plate is formed in the leading edge and the trailing edge by the semicircle which makes thickness of the plate a diameter. And application investigation was performed in order to use the plate as a rudder of a submarine. Movement speed was made into 1 knot (0.5 m/s) supposing a late velocity at the time of entry into port. The Reynolds number corresponding to the length (cord length c) and velocity of a plate was Re = 3.4×10⁵. In calculation, the angle of attack of the plate was changed from 0 degree to 90 degrees, and a numerical simulation was performed. The time history of the fluid force of acting on an airfoil, and the flow pattern were investigated. As a result of numerical experiment, as compared with NACA0012 airfoil, the plate was understood that a separation tolerance angle is large. The variation of a flow pattern and the variation of fluid force which are based on changing an angle of attack were found.