The boiling heat-transfer performances of R1234ze(E)/R152a (0.4/0.6 by mass) flowing inside a horizontal micro-fin tube of 9.52 mm outer diameter were researched by experiment. Under the experimental conditions of mean vapor quality between 0.02 and 0.98 with the mass flux of 50 similar to 100 kg/(m(2)center dot s), saturation temperature from 12 to18 degrees C and heat flux from 5 to 20 kW/m(2), and the impacts of mass flux, heat flux, saturation temperature, and mean vapor quality on flow boiling heat-transfer coefficient (HTC) and frictional pressure drop were mainly investigated; furthermore, the impact of mass transfer resistance on flow boiling process was discussed. The results indicate that R1234ze(E)/R152a obviously reveals the dry-out phenomenon in the flow boiling process, the boiling HTCs increase as the saturation temperature and heat flux, decrease and then increase as the mass flux; the frictional pressure drop rises as the mass flux and declines as the saturation temperature, while the frictional pressure drop is scarcely affected by the heat flux; it is also found that the boiling HTCs take on a decreased trend whole within the entire range of mean vapor quality, which implies that the mass transfer resistance brings about the heat-transfer degradation during the flow boiling process.
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