Developing a stable microchannel flow boiling heat sink with a venting membrane

Microchannel flow boiling can dissipate high heat fluxes, but it may face issues such as excessive pressure drops and flow instability due to the rapid bubble expansion in microchannels. In this study, we developed two types of membrane-venting heat sinks featuring either open microchannels (MV-OMC) or closed microchannels (MVCMC). Experiment revealed that MV-OMC not only effectively reduced pressure drop but also mitigated flow instability contrasted with MV-CMC. Additionally, the impact of system pressure, inlet temperature, and flow rate on MV-OMC's performance had been discussed in detail. Reducing system pressure enhanced boiling heat transfer but aggravated pressure drop and flow instability. Moreover, increasing the inlet temperature significantly suppressed flow instability at high heat flux. At an inlet temperature of 50 degrees C and a flow rate of 947.9 kg/ (m2 & sdot;s), 2 & sdot; s), the MV-OMC heat sink in negative pressure operating status stably dissipated a heat flux of 488.6 W/cm2 2 with small fluctuations of +/- 0.2 degrees C in solid temperature and +/- 0.2 kPa in pressure drop. In all, this investigation revealed the potential of membrane-venting microchannel heat sinks in high heat flux scenarios where stable dissipation was required.