THE COOLING CAPACITY OF NATURAL GASES FOR CIRCULAR/RECTANGULAR GEOMETRIES BY IMPINGING JET

Abstract

In this work, influences of the variety of parameters on the heat-transfer forced convection of two confined impinging jets, such as inlet geometry and mass-flow rate, have been investigated numerically. Simulations were done using a 3D k - ε model for incompressible flow on two jet exit geometries comprising rectangular and circular jets at the dimensionless jet-to-plate distance of 2. A finite-volume method was employed to discretize the equations. Local Nusselt number was obtained for various mass-flow rates and geometries for air and pure gases of oxygen, nitrogen, argon, and carbon dioxide at a dimensionless jet-to-plate distance of 2. As the mass-flow rate increases, heat-transfer enhancement is obtained. The CO₂ gas has the highest level of the Nusselt number in comparison with others, and around 40% increases the rate of heat transfer compared to the air; thus, it could be beneficial in the cooling process rather than other gases. Also, this study revealed that the forced-convection heat transfer in the circular jet has a higher amount than the rectangular jet.