ABSTRACT The nucleated pool boiling heat transfer experiments for plain and five different reentrant cavity copper tube surfaces in saturated R134a, R32, and R600a have been carried out. The experiments are carried for heat fluxes ranging from 6.92 to 51.71?kW/m2 at saturation temperatures of 7°C and 10°C. A significant increase in the boiling heat transfer coefficient has been observed for all tube surfaces with the reentrant cavity. The nucleate boiling heat transfer coefficient for R134a, R32, and R600a is 1.2–2.8 times more than that for plain tube surfaces. A correlation for reentrant cavity surfaces has also been developed.
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