Single Component Two Phase Flow through a Converging Nozzle in Critical State

Abstract

Single component two phase flow in a state of thermodynamic non-equilibrium has been investigated analytically. It is difficult in general to determine mass and heat transfer through the interface as vaporization and condensation. As the first step to reveal the characteristics of these complicated two phase flows occuring in variable area channels or in high speed flow, the analysis for the process of phase change between the liquid and the vapor is taken by the theoretical method, approximately, without any empirical conditions. The result of numerical calculation for steam-water critical flow in a state of thermodynamic non-equilibrium is shown to be in the range of 0.6 - 8.6 MPa saturated pressure at a nozzle inlet, and is compared with the equilibrium flow and experimental data on the critical flow in the past.