S0504-1-5 Flow visualization and velocity measurement of a two-dimensional jet at low Reynolds numbers

Abstract

A two-dimensional jet is a basic, free shear flow. The analytical solution of velocity for a laminar tow-dimensional jet was given by Bickley. The critical Reynolds number of the two-dimensional jet was obtained using linear stability theory. However, the characteristics of the jet at very low Reynolds numbers have not been confirmed by an experiment, because it is very difficult to conduct the experiment. We deal with the two-dimensional jet within the range of Reynolds number from 10 to 200. The jets were visualized by smoke and the velocity was measured by a hot wire anemometer. From the flow visualization of the jet flows, the flow pattern of the jets may be classified to 3 kinds, and it is expected that the critical Reynolds number is between 50 and 60. Mean velocity variations on the streamwise direction are partially in agreement with the Bickley's jet.