An Investigation into the Effective Thermal Conductivity of Vapour Chamber Heat Spreaders

Vapour chambers are a promising solution to thermal spreading issues associated with high heat flux devices. This paper presents a numerical investigation into vapour chamber heat spreaders using the concept of effective thermal conductivity. A 2D axisymmetric model was built and thermal performance was analysed through variation in effective thermal conductivity. The vapour chamber had more even temperature distributions and lower spreading resistances than an equivalent copper spreader. At a larger radius the superiority over copper was less distinct as only a 7% reduction in spreading resistance was observed compared to 20% reduction at a smaller radius. The effective thermal conductivity was identified as the limiting factor for this case and thus further advances are required to improve the spreading performance of vapour chambers.