摘要：【中文摘要】 本文以直熱式空氣源熱泵熱水器中的套管式冷凝器為研究對象,討論了在設計工況下,由于過冷度變化而引起的冷凝器過熱區、兩相區和過冷區的傳熱溫差、傳熱系數、換熱量、換熱面積以及COP相對值的變化,為研究不同過冷度下冷凝器的傳熱性能提供了方便而有效的方法。 【英文摘要】 The double-pipe condenser of instantaneous air-source heat pump water heater was taken as the research object.According to certain design criteria,the variations of heat transfer temperature difference,heat transfer rate,heat transfer coefficient,heat transfer area,and the relative value of COP in the superheating zone,the double phase zone and the sub-cooling zone were discussed with the variation of sub-cooling degree of condenser.A convenient and effective method was provided to research the heat transfer performance of condenser at different sub-cooling degrees. 【中文關鍵詞】 套管式冷凝器; 過冷度; 傳熱溫差; 換熱量; 換熱面積【英文關鍵詞】 double-pipe condenser; sub-cooling degree; heat transfer temperature difference; heat transfer quantity; heat transfer area