Shape optimization of nucleating wet-steam flow nozzle

Abstract This paper works on the optimization of wet-steam nozzle shape. Employment of Navier–Stokes viscous flow equations which are coupled with a two equation k – ω based SST turbulent model, with a finite volume discretization and fully Eulerian reference frame for both phases provide an appropriate numerical modeling to this type of flow. Droplet phase change model, which employs homogeneous nucleation theory, is used for predicting the appearance of droplets. Two phases are coupled through heat and mass transfer. Properties of water vapor and liquid are described by means of IAPWS equations. The results of numerical modeling are compared with experimental data. Response surface model is used to carry out sensitivity analysis of design parameters and genetic algorithm is applied. Different optimization tactics are analyzed using wet-steam flow results to achieve optimized shape, and the pros and cons of each are discussed.

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