Numerical analysis on heat transfer characteristics of a multi-vapor channel vapor chamber with novel ultra-thin composite wick

Abstract

A three-dimensional numerical model is established to predict heat transfer characteristics of a multi-vapor channel vapor chamber (VC) with novel composite wick. In order to validate the numerical model, the surface temperature of the VC is compared with the experimental results. The mass flow rate distribution of working fluid in the wick is obtained. And the effects of the height of the vapor channel on the velocity, pressure drop of the vapor and total thermal resistance are investigated at different heating powers. The velocity, pressure drop of the vapor and total thermal resistance have the same variation trend, which are all inversely correlated to the height of the vapor channel respectively. However, the reduction of the thermal resistance of the vapor decreases as the height of the vapor channel increase. At last, the conduction-based model for the vapor chamber is put forward and the effective thermal conductivity of the vapor channel is derived. The maximum relative error between the VC surface temperature prediction based on the conduction model and the experimental data is less than 5 %.

Keywords

• Composite wick
• Ultra-thin vapor chamber
• Spiral woven mesh
• Conduction-based model