Simulation analysis of steady-state heat transfer characteristics of combined jet impingement cooling on the wall

Abstract:

Jet impingement is a heat exchange method with high local heat exchange efficiency, and it is very important for engineering application. In this study, by means of fluid simulation software Fluent, a jet impingement cooling model with multiple nozzles was designed, the steady-state heat transfer characteristics of the process was studied when the combined jet impinges on the wall surface vertically and obliquely, and the influence of nozzle inclination angle and distance on the heat transfer characteristics of the wall was discussed. It is found that as the inclination angle of the oblique nozzle increases, the average Nusselt number of the combined jet gradually increases and then decreases. The combined jet inherits the advantages of the single straight jet and the oblique jet. It ensures heat transfer efficiency in the stagnation zone, improves the heat transfer efficiency downstream of the jet effectively and makes the wall temperature distribution more uniform in the meantime. When the oblique nozzle is close to the straight nozzle, the overall heat transfer characteristics of the combined jet are similar to that of the single oblique jet. When the distance between the inclined nozzle and the straight one is increased along the horizontal direction and the longitudinal direction, the average Nusselt number of the wall increases, the two high-temperature regions upstream from the nozzle area shift to the downstream, and the cooling efficiency improves significantly.