On the Development of a Vortex Street in a Free Convection Boundary Layer

Abstract

The free convection boundary layers of ethyleneglycol or water along a vertical cylinder are observed. A laminar layer transits to a vortex street layer at G_rP_r≒4×10⁹, and then to a turbulent layer at G_rP_r≒10¹⁰. In the vortex street layer, the geometrical configuration of which is similar to that of Karman vortex street, the pitch of the vortices and the number of the vortices developed per unit time are kept constant respectively. Then it is tried to analyse these experimental data theoretically. Though the theory is very simple, the results are in nearly good agreement with the experimental data.