Experimental investigation on thermal performance of aluminum vapor chamber using micro-grooved wick with reentrant cavity array

Highlights: • MGRA vapor chamber holds fast temperature response with low start-up heat load. • Stable thermal resistance during the test range and heat transfer limit > 150 W. • Good anti-gravity performance with reduced thermal resistance yielded at 30°. • Hardly affected by the cooling flow rate higher than 10 L/h. • Competitive thermal performance compared with other ones in literatures. - Abstract: In order to provide efficient thermal management for high-power electronics while keeping the light weight and compact physical size of the devices, a thin aluminum vapor chamber using micro-grooved wick with reentrant cavity array (MGRA) was developed. The MGRA was featured with high-aspect ratio micro-grooves for capillary capacity enhancement and reentrant cavities for phase change facilitation. The start-up performance, thermal resistance, temperature distribution of the vapor chamber, as well as the effects of heat load, operational orientation and cooling flow rate on its performance were investigated. The MGRA vapor chamber yielded a fast temperature response and low start-up heat load. Besides, the thermal resistance remained stable from 0.055 to 0.074 K/W. It also showed a good anti-gravity performance, with the minimum thermal resistance reached at the inclination of 30°. In addition, the cooling flow rate had little effect on the thermal performance of the chamber, despite the decrease of wall temperature with increase of flow rate. In order to justify the advantage of employing MGRA as enhanced wick, the MGRA vapor chamber was compared with others reported in literatures. The results indicated that this vapor chamber was well suited for thermal management of compact high-power electronics under various operational conditions.