A numerical study of two-phase transonic steam flow through convergence-divergence nozzles with different rates of expansion

다국어 초록 (Multilingual Abstract)

During transonic flow of steam in divergence nozzles, flow first supercools and then nucleates to become two-phase droplet flow. This phenomenon especially occurs in the last stages of steam turbines and affects performance.
In this research, a numerical scheme for two-phase flow in nozzle passages is developed. An Eulerian-Eulerian reference frame is used for both phases. The shear stress transport turbulence model is used to model the Reynolds stresses appearing in the averaged Navier-Stokes equations. The homogeneous nucleation model is applied for the mass transfer in the transonic conditions. In this paper three nozzles with different rate of expansion are employed to be under study.
Overall pressure ratio (static to total pressure) and droplet size are compared with the experimental data and good agreements are observed.

참고문헌 (Reference)

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