Comparison of Different Single-Phase Liquid Jet Impingement Cooling Configurations in the Context of Thermal Management in Power Electronics

Abstract

Jet impingement has been an attractive cooling option in a number of industries over the past few decades. Over the past fifteen years, jet impingement has been explored as a cooling option in microelectronics. Recently, interest has also been expressed by the automotive industry in exploring jet impingement as an option for cooling power electronics components. The main purpose of this paper is to compare the different single-phase jet impingement configurations, which have been reported in the literature, primarily from a heat transfer viewpoint. The discussion is also from the viewpoint of the cooling of IGBTs (insulated-gate bipolar transistors), which are found in inverters in hybrid automobiles. In the literature, single and multiple submerged as well as free-surface jets have been investigated. A number of correlations for heat transfer from the simulated chip surface have been presented. These correlations, as well as the results from them will be discussed in detail. We will also present results for the average heat transfer coefficient on the chip surface as a function of both coolant mass flow rate as well as velocity. All the results presented are for water jets. A numerical study of some of the single-jet cooling configurations (free-surface as well as submerged) is also performed and the CFD results are compared to the results obtained from the empirical correlations. The pressure drop associated with these jet impingement systems is also examined briefly. From the standpoint of practical implementation, high velocity jets have the potential to erode the material on which they impinge. This paper will briefly discuss erosion rates associated with jets impinging on aluminum and copper.