Additively Manufactured Hybrid Two-Phase Cold Plate

The performance of a capillary-driven two-phase cold plate (CP) for thermal management of high heat flux electronic devices was investigated. The CP was a key component of a hybrid two-phase cooling system (HTPCS). The HTPCS operated with the refrigerant R245fa and integrated the benefits of a pumped two-phase cooling with a capillary-driven two-phase cooling. The significance of the present study is to fabricate the CP integrated with evaporator wicks through one single additive manufacturing (AM) process. The CP was a compact enclosure including eight heaters located on both sides of the CP. The evaporator wicks were lattice structures, and individual heater was cooled down by its own evaporator. Compared to the CP without evaporator wicks, the capillary-driven CP (CDCP) led to 39% enhancement in the upper limit heat flux, as well as over 44% improvement in the non-uniformity of the thermal resistance of the CP. The equivalent heat fluxes achieved by the CDCP was 203–212 W/cm² over areas less than 0.1 cm². The measured thermal resistances at those ranges of heat fluxes were ∼ 0.16–0.30 K-cm²/W, while operating within a low pumping power below 0.3 W.