摘要
•A novel thermal module proposed to replace current heavy pin–fin heatsink module.•The novel module consists of an ultra-thin vapor chamber with a plate-fin heatsink.•Ultra-thin vapor chamber provides excellent spreading for plate-fin heatsink.•Fan power reduces to only 1/9 and weight less than 1/2 with Al plate-fin heatsink.•Plate fins’ wide spacing and smooth structure can operate long without blockage.
A novel ultra-thin vapor chamber (UTVC)/plate-fin heatsink module is designed and tested for cooling a block up-converter (BUC) with GaN chips. The UTVC adopts a composite mesh-groove-powder wick. The plate-fin heatsink is made of either copper (Cu) or aluminum (Al) alloy. The Cu/Al heatsink has a fin thickness of 0.8/1.5 mm, a fin spacing of 2.7/2.5 mm, and a height of 30/28.8 mm. Both 140 × 120 mm2 heatsinks are coupled with an upward-blowing 120 × 120 × 25.4 mm3 axial fan running at 2200 rpm. The original 120 × 120 × 38 mm3 axial fan runs at 3600 rpm in the commercial BUC product. First, the UTVC is shown to endure a maximum heat flux of 140 W/cm2 of one of the GaN chips; Then, the UTVC is tested successful under a heating area of 30 × 30 mm2; Finally, the three heatsink modules are tested under 260 ± 5 W, the maximum total dissipation of the chips. With a Cu or Al plate-fin heatsink, the temperature differences between the heater center and the environment are 70 ℃ and 78 ℃, respectively, while that of the original pin–fin heatsink is 72 ℃. The original heavy pin–fin heatsink tends to break down after operation at outdoor environment by corrosion and dust blockage, and the fan power is 9 times higher than for the plate-fin heatsinks. The UTVC/Al plate-fin heatsink can replace the pin–fin heatsink with advantages of cheaper, lighter, less power consuming, and longer life. This work opens up the application of UTVCs in the thermal management of satellite communication devices.