Application of Three-Layer Model Analysis to Single-Component Two-Phase Critical Flow through a Converging Nozzle : Comparison of the Experimental Results for Steam-Water Mixture and Carbon Dioxide with the Calculated Results

Abstract

A two-phase critical flow with phase change through a converging nozzle is investigated and discussed in terms of the applications of three-layer model analysis which has already been reported for a case of two-component two-phase flow by Ochi and Ayukawa. In the theoretical analysis of a single-component two-phase flow during rapid phase change, there are some difficulties arising from the modeling of a complicated flow pattern at the interface. The calculated results using our proposed model are in good agreement with experimental data of the flow rate and the pressure of carbon dioxide or steam-water mixture flows. The flow properties in each layer through the channel are discussed in comparison with the completely separated flow or the homogeneous flow model. It is found that the three-layer model is a useful method for single-component two-phase flow undergoing rapid change of state in variable-area channels.