Optimization and Application of Analytical Model to Define Heat Carrier Parameters in T-Joints of Pipelines

Setting of the analytical model is executed to define the heat carrier local parameters in T-joints of the light-water reactor plants. The LES-type (large eddy simulation) turbulence model is used. Influence of such factors as sub-grid models, mesh resolution and in-time integration steps on the results is analyzed. Recommendations for parameters selection of computational model are specified. The estimation of possibility to scale computational models on geometric and operating parameters is carried out. Possibility to use the reduced analysis grids for defining time-averaged temperature and velocity of the jet flow in T-joints at constant Strouchal number, with mixing zone situated in branch pipe, is considered, too. Possibility of existence of low-frequency temperature variations in the liquid is shown. Calculations are performed on full-scale modes and geometric parameters.

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