Flow Boiling Heat Transfer Characteristics at Inlet Two-phase Flow Condition in Radial Expanding Channel Heat Exchanger

摘要

Conventional microchannels heat exchangers can barely endure two-phase (TP) flow inlet, and subcooled liquid is always required to guarantee the efficient operation of system. To solve multi-heat sources cooling issue, a type of circular radial expanding minichannels heat sink (REMHS) utilizing flow boiling of deionized water is proposed in present work, under the condition of TP flow inlet ranging from 0.01-0.53. Under TP flow inlet, the proposed REMHS maintains a stable and high flow boiling performance without occurring heat deterioration, the flow distribution is uniform and the heat transfer capability displays a good symmetry. Six classic flow boiling heat transfer correlations are compared with the experimental results, Li & Wu's correlation gives a good prediction on all the measured data with MAE of 21.1%. By examining the thermal independence of REMHS connected in series, the proposed REMHS is confirmed to be applied to multi-heat source cooling.