本文采用试验的方法对扁平管内的负压蒸汽冷凝过程进行了研究。研究结果表明,这类扁管的特殊结构使得管内的蒸汽充满度高,冷凝液占据整个流动截面的份额小,流动顺利,阻力小,是很好的有利于冷凝液流动的管型。研究结果给出了这类扁平管的管内冷凝流动摩擦阻力的计算方法,为这类管型在空冷凝汽器的应用提供了设计依据。 In this paper, the experimental method of vacuum tube in a flat tube condensation process were studied. The results show that the special structure of this type of flat tube makes the steam in the tube full, the condensate occupies the small part of the entire flow cross section, flows smoothly, and has low resistance. It is a good tube type that is conducive to the flow of condensate. The research results show the calculation method of the flow friction resistance of the tubes in the tube, and provide the design basis for the application of these tubes in the air-cooled condenser.