Study on heat transfer characteristics and pressure drop in droplet-shaped array microchannel
Novec-649 was used as the test medium to experimentally investigate the boiling heat transfer characteristics in microchannels under different operating conditions.The results show that for different inlet temperatures,inlet dryness and mass flow rates,the heat transfer coefficients show a tendency of increasing and then decreasing with the increase of heat flow density;the effect of inlet temperature on the heat transfer coefficients is not obvious,and the increase of mass flow rate promotes the heat transfer,and the heat transfer coefficients increase by a maximum of 14.7％when the mass flow rate is increased from 1.6 to 2.4 g/s;whereas the increase of the inlet dryness and hydraulic diameter inhibits the heat transfer.Moreover,the pressure drop shows an increasing trend with the increase of inlet temperature,inlet dryness and mass flow rate,but the increase of hydraulic diameter suppresses the pressure drop,which exceeds the maximum by a factor of 2.3.
MicrochannelDroplet-shaped arrayHeat transfer coefficientPressure dropHydraulic diameter
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NSTL
万方数据
