Flow Visualization Across Main Flow

Flow visualization for the study of two dimensional flows has been commonly used. Because flow is similar on all planes normal to the forward direction in a plan view, a single such plane only need be visualized. In three dimensional flows, visualization in transverse planes normal to the forward direction, should provide additional information concerning velocities and vorticity in those planes. A simple experimental arrangement using prisms and a system of illumination is developed to obtain a view of the transverse planes, so that fluid motion in these planes can be observed; an end-on picture of the flow is thus obtained. Photographic records obtained by using this technique indicate the possible use of the arrangement in the study of secondary motion in three dimensional fluid flow.