Numerical study on cooling of high-power laser diode arrays using slot jet array impingement

Abstract

Thermal design shows significant effects on energy conversion efficiency, lifespan and beam quality of high-power laser diode arrays (HPLDAs). In this study, a slot jet array heat sink (SJAHS) is designed to improve the cooling performance of HPLDAs, and numerical simulations were conducted to optimize the flow and heat transfer in the heat sink. Flow passages inside the heat sink ensured that the coolant is allocated to every jet uniformly. The jet geometry is optimized to enhance the heat transfer. When the working fluid is assumed as water at 293 K inlet temperature and at a flowrate of 800 mL/min, the heat sink is capable of removing 150 W heat over an area of 15 mm2 with a maximum temperature increase of 52.75 K from the coolant inlet to emitters. It means that the emitter-to-coolant thermal resistance is 0.35 K/W without considering the interface thermal resistance. The corresponding pressure drop is 361 kPa. Compared with the existing microchannel heat sink, the numerical results implied that this new heat sink possesses a better cooling performance.