| 摘要 |
PURPOSE:To improve heat transfer performance, in the flat pipe wherein many plate shaped inner fins are provided in a slant state in a heat transfer pipe, by differentiating the slant angles in the respective regions of liquid, gas, and boiling or condensation. CONSTITUTION:An evaporator comprises a tube element 2 which becomes a refrigerant evaporating chamber 9 having many plate shaped inner fins 1, corrugated fins 3 between them, both side plates 4, and refrigerant inlet and outlet chambers 6 and 8 at the upper and lower parts. The slant angle of the fins 1 with respect to the flowing direction A of the refrigerant is beta 6 deg.. The fins 1 comprise the fins 1a and 1c in the liquid region C and the gas region E and the fins 1b in the boiling region or condensing region D wherein the reverse slant angle is gamma=6-18 deg.. In this constitution, since the liquid refrigerant corresponding to the thermal load distribution in the direction B of an air flow is supplied, the heat transfer surface can be effectively used. Since a thermal boundary layer is not developed through the entire region, the heat transfer performance can be improved. |
