Experimental and numerical heat transfer analysis of heat-pipe-based CPU coolers and performance optimization methodology

[Display omitted] •Influence of orientation on performance of heat-pipe-based coolers is evaluated.•High thermal resistance on the air-side obscures the effect of HP inclination.•CFD simulations are performed and validated using experimental data.•Geometry optimization methodology is proposed and showcased.•Proposed methodology can reduce costs, R&D time and decrease product’s weight. This paper presents an experimental and numerical heat transfer analysis of heat-pipe-based CPU coolers and a performance optimization methodology. The first part of the study focuses on the performance of two commercial HP-based CPU coolers under inclination angles of 0°, 90° and 180°. The results show that the 90° orientation provides the best thermal performance. The influence of heat pipe orientation on the performance of the entire system is obscured due to the much higher thermal resistance on the air-side of the cooler. A fourfold increase in air volumetric flow rate has only a minor effect on the cooling performance enhancement with a reduction of the thermal resistance from 0.11 K W−1 to 0.074 K W−1 at the highest heating power. In the second part of the study, heat transfer numerical simulations of the finned part of a cooler were performed and validated using experimental results. The output of the simulation is a 2-D temperature field, which is used as an input for the optimization methodology based on fin effectiveness and fin efficiency. Optimizing the fin geometry by removing unnecessary material yielded a 23% increase of the fin efficiency and decreased the weight of a fin by approx. 30%, proving the usefulness of the proposed methodology, which helps reduce costs, weight and development time of finned HP-based coolers.