Evaporation heat transfer and pressure drop of CO 2 /DME mixture in a horizontal tube (original) (raw)

An experimental investigation on the effect of CO 2 concentration in CO 2 /DME mixture of in-tube evaporation has been carried out for 3.6 m long smooth and helical micro-fin tubes with an outer diameter of 5 mm. Measured local heat transfer coefficients and pressure gradients are reported for mass fluxes 100, 200 and 300 kgm -2 s -1 with CO 2 concentration of 10%, 25% and pure DME for both tubes. Results from this work are compared with some existing and renowned correlations of smooth and helical micro-fin tubes. Differences in heat transfer mechanisms between smooth and micro-fin tubes are discussed.