Experimental study on dynamic heat transfer characteristics of microchannel two-phase loop with latent heat storage

High-power equipment frequently faces the specific challenge, such as operating with intermittent high heat flux under limited cooling resources. However, traditional single-cooling approaches are inadequate to meet this specialized heat dissipation requirement. To address this issue, a novel microchannel two-phase loop with latent heat storage has been proposed for dissipating high heat flux in a microchannel evaporator and storing heat in a latent heat exchanger (LHE). Dynamic thermal performance of the two-phase loop is systematically explored, with a special focus on thermal response behaviors of microchannel evaporator and LHE unit at three heating modes. It indicates that the novel system can effectively deal with thermal shock of instantaneous high thermal load. Two characteristic thermal response modes have been found, i.e. delayed response mode and real-time response mode. The delayed response mode would quickly utilize the heat storage capacity of LHE and shorten melting duration, accompanying with an increase of 147.2 % in the peak storage rate and a decrease of 60.2 % in working time. To enhance the thermal performance of LHE, a novel venation-finned porous network LHE is employed and experimentally tested. Due to its efficient heat transfer pathways, this design improves the melting heat storage rate and eliminates heat transfer lag. As a result, the maximum temperature difference between two typical vertical testing points is only 0.9 degrees C, which demonstrated the more uniform temperature distribution.