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通过对一凝汽器的二维数值模拟,研究了湍流黏性系数和湍流扩散系数对凝汽器流动与传热特性的影响。结果表明,湍流参数的取值,对凝汽器不凝结率的计算影响较大,对壳侧压降也有一定影响。在凝汽器数值模拟中,采用两方程的RNGκ-ε模型米确定湍流参数,在管束区内部形成湍流参数较大的区域,能更准确描述凝汽器内的复杂流动。与常湍流参数的模拟相比,采用RNGκ-ε模型计算的蒸汽不凝结率增大。“,”Two-dimensional numerical investigation was carried out on a steam condenser to investigate the effects of turbulent viscosity coefficient and turbulent diffusion coefficient on the simulation results of flow and heat transfer performances.The results show that the turbulent parameters significantly influence the non-condensation rate,and also affect the shell side pressure drop.RNG k-εtwo-equation model was used for turbulent parameters calculation.The numerical simulation shows that an area with a bigger turbulent parameters exists in the tube bundle,i.e., this model can more effectively depict the complicated turbulent flow.Compared with the results simulated with constant turbulent parameters,the simulated non-condensation rate of stream by the RNG k-εtwo-equation model becomes larger.