Fabrication and heat transfer performance study of aluminum-based grooved composite porous enhanced boiling structure

Abstract

As high-power electronic devices trend toward higher power, miniaturization, and integration, aluminum-based phase-change heat transfer has garnered significant attention for enabling efficient and lightweight thermal management. However, existing aluminum-based porous boiling heat transfer enhancement structures still face challenges such as inefficient gas-liquid separation during boiling, difficult bubble escape, and consequently poor heat transfer performance. To address these issues, this study proposes an aluminum-based groove composite porous enhanced boiling structure (A-GCPS) with gas-liquid separation channels. The macroscale groove structure facilitates gas-liquid separation and enhances convective disturbances, promoting bubble escape, while the microporous structure provides additional boiling nucleation sites and improves capillary performance. The enhanced capillary performance ensures timely liquid replenishment to the heating surface, significantly improving boiling stability and heat transfer performance. A saturated pool boiling heat transfer test platform was designed and built. Experimental results show that the critical heat flux (CHF) and heat transfer coefficient (HTC) of A-GCPS reach 150.50 W/cm² and 38.31 kW/(m²·K), respectively, representing increases of 165.88 % and 69.14 % compared to a flat aluminum plate and a 70.1 % CHF improvement over traditional sintered aluminum powder structures (A-EBS_C), outperforming most aluminum-based enhanced boiling structures in related studies. Visualization of bubble dynamics reveals that the CHF enhancement and delayed boiling crisis in A-GCPS primarily result from continuous bubble detachment in the gas channels and sustained liquid supply in the liquid channels of the groove structure. This aluminum-based enhanced boiling structure with gas-liquid separation channels offers an effective thermal management strategy for lightweight, high-power electronic devices.