Experimental Research on Heat Transfer of Confined Air Jet Impingement with Tiny Size Round Nozzle in High Density Electronics Packaging Model

As the heat generation density of electronics packaging grow fast during recent years, the problem of heat dissipation of electronics become the obstruction of development of electronic packaging industry, which accelerated the research and development of heat transfer on the direction of microcosmic. In this research, an epoxy resin laminate heated by heating element was used as the heat transfer surface of simulated chip, and the thermocouples were mounted symmetrically along the diagonal of the laminate to measure the temperature distribution of the surface. Air jet, driven by a small pump, comes from round nozzles (1.5mm and 1mm in diameter) and impinges on the heat transfer surface with middle and low Reynolds number. The parameters such as Reynolds number and height-to-diameter ratio was changed to investigate the radial distribution of Nusselt number and the characteristics of heat transfer in stagnant section. This experimental research gives useful information for the application of air jet impingement to the cooling of electronics packaging