NUMERICAL SIMULATION OF LAMINAR FLOW AND HEAT TRANSFER FOR LIQUID JET IMPINGEMENT COOLING OF A CIRCULAR HEAT SOURCE WITH ANNULAR COLLECTION OF THE SPENT FLUID

Abstract

Axisymmetric, laminar jet impingement cooling of a circular heat source has been simulated under conditions for which discharge of the spent fluid may influence heat transfer from the source. The simulation specifically addresses an annular configuration for which the jet is discharged from a circular tube and, after impingement, is redirected 180° to exit through an annular passage. The flow is strongly influenced by two recirculation zones located adjacent to the jet and in the corner formed by intersection of the outer wall of the annulus with the heater/substrate surface. For jet velocity profiles that are parabolic or uniform, respectively, the radial distribution of the local Nusselt number is characterized by a local maximum or minimum at the stagnation point. If the outer wall of the annulus intersects the outer edge of the heater, the Nusselt number exhibits a local maximum near the edge, irrespective of the jet velocity profile. Parametric calculations have been performed to assess the effects of Reynolds number, Prandtl number, and pertinent geometric parameters on flow and thermal conditions.