The Numerical Investigation of Groove Parameters in a Bionic Vapor Chamber

Abstract

As the high heat flow density electronic devices become more miniaturization, lightweight, and high integration, the thermal control of these devices also be challenged. This paper proposes a bionic vapor chamber (B-VC) with a patterned leaf vein separating the liquid-vapor channel, and study the performance of B-VC under different groove parameters utilizing a 3D CFD model. The results demonstrate that the B-VC with fractal structure is better than that without fractal structure in heat transfer performance, but there is a tradeoff with a higher total pressure drop. This tradeoff is further apparent in the B-VC with the increase of groove branch level and the groove circumferential width. The increase of the groove branch level from one to four reduces the maximum temperature difference at the condenser by 25% to 73%, but the total pressure drop has increased by 1% ~10% compared to the without fractal structure. The similar trend can be seen when the B-VC with circumferential groove compared to that without circumferential groove. A groove angle of 32° has the minimum total thermal resistance, and a higher groove angle can decrease 22% to 49% in the maximum temperature difference in the top condenser surface with minimal impact on the overall pressure drop. Finally, the heat transfer performance improves as the groove trunk width increases, and a groove trunk width of 2mm allows for a minimum total pressure drop.

Keywords: vapor chamber, leaf-veinlike structure, groove parameters, separation of liquid and gas flow channel