Abstract: Water surface evaporation coefficient,roughness, eddy viscosity and thermal diffusion coefficient are important parameters in the process of numerical simulation of warm water drainage. Correct selection and calculation of them may affect the accuracy of simulation results directly. Taking a coastal nuclear power plant as an example, the effect of parameter selection on simulation results of the maximum temperature rise area of 1 ℃was analyzed. The sensitivity of each parameter is also analyzed. It expects to provide reference for the numerical simulation of warm water drainage in future coastal nuclear power projects.

Key words: Warm water drainage, Numerical simulation, Sensitivity