水平細管内の流動と沸騰熱伝達に関する研究(機械工学科)

Abstract

Heat transfer coefficient and pressure drop for refrigerants R-123 are measured in horizontal small tube. The stainless steel tube of 1.1mm inside diameter, 305mm heated length is used for the test section. As ranges of the main experimental parameters, heat fluxes are 0.5-33kW/m^2; mass velocities 110-3400kg/m^2s; and inlet temperatures 18-30℃. The experimental result presented that the boiling heat transfer coefficients are between 3 and 12 times as large as the single convective heat transfer coefficient. It is also presented that the two-phase frictional pressure drop could be predicted by following relation within ±20%. ΔP_F/ΔP_<Vo>=1.68x^<1.10>_<exit> Where, ΔP_<Vo> is pressure drop for the total flow of fluid having the vapor properties at test section exit.