Numerical study on condensation of R134a refrigerant in microchannel

The action of capillary forces during flow condensation of refrigerant R134a in rectangular microchannel is considered numerically using the annular flow model. It was shown that significant accumulation of the liquid occurs near the channel corners and causes the heat transfer enhancement. The heat transfer related to the condensation is taken into account assuming the interface temperature is at saturation. The numerical method is validated against experiments and well predicts the flow patterns inside the microchannel and average heat transfer coefficients.