Abstract
Carbon dioxide attracts attention as a natural refrigerant, and two-phase ejector is expected to improve the COP (Coefficient of Performance) of carbon dioxide heat pump. This research is aimed to clarify the characteristics of the super sonic two-phase flow of carbon dioxide in a nozzle, which is one of the most important elements of the ejector. In the present study, critical mass flow rate and pressure distribution was measured, and analyzed. While the experimental results of mass flow rate agreed well with the theoretical prediction, the experimental pressure distribution was higher than the theoretical one.
