수소연료전지차 이젝터의 유동특성 및 유량예측 해석

Abstract

Fuel cell electric vehicle(FCEV) using polymer electrolyte membrane fuel cell(PEMFC) consumes the hydrogen as fuel. The ejector with very simple structure in FCEV enhances the stack efficiency and supplies the humidity to hydrogen through recirculation system. Thus the ejector has been applied to many industrial fields such as aerospace, machinery as well as FCEV. This study aims to investigate the flow characteristics and prediction of flow rate for ejector in FCEV. As the results, as the inlet pressure of ejector was increased, the velocity in nozzle was decreased, on the other hand, the velocity in mixing section and diffuser was increased. In analysis conditions of this study, the flow rate of hydrogen was affected more density than velocity. In cases of 4∼6 bar, the flow rate of hydrogen was supplied to stack about 0.15 times compared with that of air. Further it showed that the flow rate of hydrogen was about 10 times larger than that of commercial vehicle in case of 2 bar.