EVAPORATIVE HEAT TRANSFER AND PRESSURE DROP OF R410A AND R32 IN SMOOTH HORIZONTAL TUBE

Flow boiling heat transfer of R410A and R32 inside a smooth horizontal tube whose hydraulic diameters are 5,6 and 7mm. The mass flux was varied from 100 to 400 , heat flux from 5 to 15 , as the saturation temperature were maintained at -30 °C and -40 °C. The effects of the imposed wall heat flux, mass flux, vapor quality on the evaporation heat transfer and pressure drop discussed as a function of vapor quality and tube length. The results from Matlab program are compared with experimental data.

Keywords:

R410, A R32, heat transfer pressure drop, horizontal tube.,

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