초음속 노즐 내에서 수증기의 비평형 응축 효과 = Effect of Non-Equilibrium Condensation of Steam in a Supersonic Nozzle

다국어 초록 (Multilingual Abstract)

Non-equilibrium condensation during the rapid expansion of steam in turbomachinery affects the flow performance. The latent heat released during the condensation process leads to condensation shock, which decelerates the flow. In the present paper, the numerical modeling of the non-equilibrium condensation in a supersonic nozzle is achieved by solving two transport equations based on the classical nucleation theory corrected for non-isothermal effects as well as the droplet growth law of Hill. The numerical model is successfully validated to be in good agreement with the experimental data. The effect of condensation of the steam in the nozzle is studied by comparing various flow properties of the steam flow with and without condensation. The results show that the exit Mach number of the nozzle is reduced by 13.5%, and that the total temperature at the exit and boundary layer thickness of the flow are increased by 11.5% and 28%, respectively, due to the latent heat released during the condensation process.

참고문헌 (Reference)

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