PREDICTION FOR SATURATED FLOW BOILING HEAT TRANSFER IN MINI-CHANNELS

A superposition correlation is proposed to predict heat transfer coefficient of flow boiling heat transfer in mini-channels. In this correlation, Reynolds number of liquid phase is presented by means of vapor velocity and slip velocity ratio. The film thickness and Bo number are taken account into this correlation. This new correlations were developed based on the conditions contained in our database. A database on experimental results of saturated-flow boiling in mini-channels includes 3839 data points, 9 different refrigerants, and covers a wide range of operation conditions from 10 independent studies. Most inner diameters in this database is within 0.5 mm and 3 mm and the mass fluxes in the database range from 50 to 600 kg /m(2)s, the heat fluxes from 5 to 123 kW/m(2), the vapor qualities from 0 to 1, and the saturation temperatures from 0 to 52 degrees C. Research advances of flow boiling heat transfer in mini-channels in recent years were reviewed. 12 available flow boiling heat transfer correlations were addressed and evaluated against the database in this study. The proposed correlation can catch 77% data within the deviation of +/- 30%. The mean absolute error of this new correlation is 20.9%.