Numerical Simulation Of Water Vapor Non-equilibrium Condensation Flow Considering The Inter-phase Slip

Supersonic flow exists in aviation, refrigeration, chemicals, and other fields. The steam in the nozzles and other equipments in the supersonic flow will have non-equilibrium condensation phenomenon, this phenomenon not only caused the corrosion of equipment but production efficiency is reduced. And the non-equilibrium condensation of water vapor forms the condensation shock wave and gas liquid two phase flow complex mixing. Mass, momentum and heat transfers between gas-liquid two-phase within a short period of time, steam thermodynamic and kinetic parameters of dramatic changes sharply and complexly. So it has caused the extensive research upsurge. In the study of previous numerical simulation, considering the complicated and calculation equations of convergence, The effects of gas-liquid two phase velocity slip is often neglected, making assumption that two phases’ velocities are equal to set up a numerical model. Velocity slip and difference between two phase have an important influence on water vapor non-equilibrium condensation flow field, especially in the initial stage, the interphase slip and interphase temperature difference will cause fluctuations in the flow field parameters. After the condensation shock, the parameters of the flow field can be adjusted back to equilibrium and steady state, condensation will not occur, and the phase velocity slip and the phase difference between gas and liquid will almost disappear. In order to further improve the numerical model of the non-equilibrium condensation flow of water vapor, slip model is established with real gas water vapor model in this paper considering the influence between the gas and liquid velocity slip and condensation. By comparison with experimental data, it is found that slip model can accurately calculate the supersonic steam flow non-equilibrium condensation flow field and condensation factors have important effects on the flow field parameters, the gas inter-phase temperature difference and the velocity slip factor can also cause the tiny fluctuation of the flow field parameter distribution. Then slip numerical model is applied to water vapor in the nozzle and jet in the supersonic flow field analysis and calculation, of nozzle under different conditions and spray the rule of the change of the parameters of flow field in the device and injector in different conditions of work performance of calculation and analysis. Considering the interphase slip model is established for supersonic steam flow equipment(such as injector, cascade involving) performance analysis and structure design, providing efficient and accurate calculation method, but also for the water vapor in the supersonic flow complex physical phenomena in the numerical simulation study provides a more perfect and reasonable simulation numerical model. The contents are as follows:(1) Slip-model is established considering the influence of the interphase slip supersonic steam flow. The numberical model is proved comperaing with the experimental data of Moore et al. and the result is also compared with the ideal gas model and condensation model without considering the effect of slip.(2) Based on Sokolov ejector design theory, an injector size calculation program is established by using IF97. The calculation results of the size of ejector is more reasonable and more corrent.(3) The supersonic water flow in nozzle is calculated and analyzed in detail, the reasons for the formation of “X-Shock” and the condensation effects of shock waves, temperature difference between two phases, and the slip distribution of convection field parameters are calculated and analyzed on the flow field parameters distribution are studied and analyzed. Then the influence of the inlet temperature, inlet pressure, and backpressure on non-equilibrium condensation is calculated and analyzed.(4) The supersonic water flow in nozzle is calculated and analyzed in detail with this slip model, the influence of outlet pressure, the pressure of motive fluid, suction fluid pressure and expansion ratio on jet performance are studied and analyzed.