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火电厂空冷凝汽器普遍使用单排蛇形翅管作为换热器基管.由于蛇形翅管翅侧几何特征复杂,管内凝结有相变相随,蒸汽到空气的传热经过多个耦合面,用计算流体动力学(computational fluid dynamics,CFD)同步模拟翅管双侧换热,存在很多困难.提出液膜表面剪切力条件下的管内冷凝模型,分析蒸汽至空气的耦合换热过程和换热面平衡条件,给出耦合换热量的计算方法.将全尺寸翅管换热的数值模拟分解成282个边界条件关联的CFD模块,实现了全管耦合换热的异步计算.对比CFD解与实验数据,两者吻合良好,表明,冷凝模型能正确仿真蒸汽冷凝,异步CFD策略是模拟全尺寸翅管双侧换热的有效方法.基于CFD解,分析了翅侧空气和管内蒸汽的流场特性.“,”The single-row flat wave finned tube is widely applied as the unit tube by the direct air cooled condenser in power plants. Caused by the complicated body geometry in fin side, the vapour condensation involving phase transition, and the heat transfer from vapour zone to air zone conjugating on several interfaces, using computational fluid dynamics (CFD) method to simulate the heat transfer in both the vapour channel and the cooling air channel simultaneously, many challenges are encountered. A mathematical model to simulate the condensation of water vapour was developed counting the interfacial shear stress, the heat balance conditions on the interfacial boundaries of the conjugate heat were presented as well as the method to calculate the conjugate heat. The numerical simulation for the full-size finned tube was carefully separated to 282 CFD modules which share same boundaries each other. Based on the 282 CFD modules, the asynchronous strategy to calculate the conjugate heat of the finned tube in overall scale was successfully carried out. The results from the CFD simulations agree very well with the experimental results, which validates the proposed condensation model, also show the great potential of the asynchronous CFD approach as an effective tool for the full-size finned tube to predict the heat transfer in both sides. Based on the CFD results, the characteristics of flow field was also investigated in terms of both the cooling air and the vapour.