Effect of Condenser Location and Geometry on Thermal Performance of a Vapor Chamber with Multiple Heat Sources

This paper theoretically and experimentally investigates the effect of condenser location and geometry on the thermal performance of a vapor chamber, as thermal management systems for electronic devices with multiple heat sources under non-uniform heat flux conditions. A weighting factor approach was applied to represent the non-uniform heat input imposed on individual heat sources. The proposed theoretical model was validated through comparison with Lefèvre’s analytical results under the same conditions and experimental data obtained under different condenser locations. It was shown that the wall temperature distribution for the separated condenser configuration was lower than for the concentrated configuration. Using the validated model, the effects of condenser geometry on the temperature uniformity and maximum heat transfer rate of the vapor chamber were analyzed under the capillary limit condition by varying the condenser aspect ratio. The results show that higher aspect ratios improve temperature uniformity due to wider condenser coverage, whereas lower aspect ratios enhance the maximum heat transfer rate by reducing the liquid pressure drop between the evaporator and condenser. Specifically, the maximum heat transfer rate reaches 72.6 W at an aspect ratio of 2.5, which corresponds to a 13.3% increase compared to 64.1 W at an aspect ratio of 8.3.