The Experimental Investigation on the Flow Past a Circular Cylinder of Finite Length Placed Normal to the Plane Surface in a Uniform Stream

Abstract

This paper treats a flow past a circular cylinder whose one end is set on a flat plate and the other free end is immersed in a uniform stream. The surface pressure distributions were measured to obtain the local drag coefficient and the mean drag coefficient, by varying the length-diameter ratio l/d from unity to 12.5. It is found that the separation point of the circular cylinder removes forward with a decreasing ratio l/d except in the neighborhood of the free end of the cylinder and the local drag coefficient changes greatly when l/d varies from 6 to 7 because a vortex street does not exist at l/d≤6. The vortices shedding frequency decreases as the free end of the cylinder is approached and it depends on both l/d and Reynolds number.