Pulsation Amplitude Influence on Free Shear Layer of a Vertical Pulsating Jet in Laminar Regime

摘要

In this study, we are proposed to find out the restrictions of the free shear layer approximations for a permanent vertical jet and a pulsed vertical jet in laminar regime by using a numerical calculation code. For this, we considered a two-dimensional air plane jet resulting in a quiescent environment. At the exit of the nozzle, the pulsating flow is imposed with a uniform temperature T0 and a velocity u=u0+a*sin (wt). The effect of the important governing parameters, such as the pulsation amplitude, the Reynolds and Grashof numbers on the flow behavior are investigated in detail. The numerical results show that the free shear layer approximations are suitable for a permanent jet in different regions; however, these approximations remain valid for a pulsed jet only in the plume region.