An Investigation On Pressure Drop And Heat Transfer In Micro-Jets Impingement Cooling Heat Sink

As miniaturization, reduction in products weight become the latest trend in electronic products development, traditional design methods and manufacturing technology fail to meet today's demands. Micro-jets impingement cooling heat sink is used to cool the high power LDA owing to the very thin hydrodynamic and thermal boundary layers in the impingement region when a jet impinges on a surface. Reasonable array of jets can develop the uniform of temperature distribution on target very much. Of the currently available coolers for electronic products with a high heat flux, micro-jets impingement cooling heat sinks are able to provide the best heat transfer performance: lowering the maxmal temperature and the temperature difference.The heat transfer for multiple jets impingement has been studied firstly for summarizing a few rules. And then a copper micro-jets impingement cooling heat sink consisting of five copper sheets is designed in this paper and the jet diameter is 0.15mm. Experiments are conducted to investigate pressure drop and heat transfer in the heat sink with water and nitrogen. The experiment results indicate that 90% pressure drop is attributed to minor pressure drop in heat sink and these results are higher than the theoretical value. The thermal resistance will drop with the increasing of pumping work and the extent of the drop will decrease when the pumping work reach some value. The maximal temperature difference between the heat-sink surface and the coolant will increase with the increasing of heat fluxes, as is same to the maximal temperature difference on the heat-sink surface. But the latter is always within a temperature range.With the excellent performance, the micro-jets impingement heat sink will grant the high heat flux LDA's demand.