| 摘要 |
PURPOSE:To reduce the friction loss of a working fluid while cutting down processing cost by forming a section corresponding to the single phase region of the working fluid in a bare pipe and forming only a section corresponding to two phase regions being accompanied by condensation or evaporation in a heat transfer pipe to which a spiral groove is processed. CONSTITUTION:A cross-fin tube type heat exchanger is mostly used as an air-refrigerant heat exchanger in an air conditioner, a refrigerator, etc. When such a heat exchanger is used as a condenser, a vapor refrigerant at a high temperature and high pressure, which is discharged from a compressor, flows into the heat exchanger as the arrow, and heat-exchanges with flowing air. There is the vapor single phase region 3, in which the vapor refrigerant is cooled, in a heat transfer pipe 1, there is the gas-liquid two phase region 4 in which heat is exchanged with condensation, and there s a liquid single phase region 5 in which the refrigerant is liquefied completely. When the heat exchanger is used as an evaporator, the refrigerant under the state of two phase of a liquid and a gas through a decompression device flows into the heat exchanger, exchanges heat, is evaporated, is brought to the state of vapor single phase and is forwarded to the compressor. In said constitution, pipe spiral groove processing is executed only to the two phase region being accompanied by condensation or evaporation, and regions except said region are formed in bare pipes, thus reducing the friction loss of the fluid, then cutting down processing cost. |
