Executive Summary : | Flow configurations that combine a wall jet and an offset jet, also known as a dual jet, are often found in wastewater disposal systems and cooling application in blown film extrusion processes. These applications require an improved understanding of the complex flow physics in a dual jet flow. When two turbulent jets with Reynolds number Re=10,000 in a dual jet flow configuration interact very closely with one another, a periodic vortex shedding occurs in the flow field analogous to a case involving flow past a bluff body. This shedding phenomenon exhibits considerable sensitivity on various geometric parameters and inlet velocity conditions for the dual jet. Although several studies are conducted on the shedding phenomenon in a turbulent dual jet, no previous study has reported this phenomenon for a laminar dual jet. Considering the facts that the nozzle plate separating the two jets in a dual jet acts as a bluff body, and a regular laminar mode of vortex shedding occurs for a circular cylinder with Re ranging from Re=47 to Re=180, the shedding phenomenon can also be expected to occur in a laminar dual jet. Therefore, the current proposal will seek an in-depth analysis on the vortex shedding phenomenon in a laminar dual jet flow. The current project will rely on numerical modelling by means of an in-house computation fluid dynamic (CFD) code solving incompressible Navier-Stokes equations. The computational results will be obtained for various geometric (gap between the two jets and jet width) as well as inlet (Reynolds number and inlet velocity ratio) parameters. To avoid the flow to become turbulent, the Reynolds number at the jets’ inlets for the proposed work will be varied up to Re=500. The output of the proposed research can be exploited to optimize the heat transfer cooling rate for microelectronic devices. |