A Novel Ejector with Water-Separator Function for Proton Exchange Membrane Fuel Cell System Based on a Transient 3D Model

Abstract

The design and optimization of the hydrogen circulation system can improve the hydrogen utilization rate and overall system efficiency of the fuel cell system. The ejector and water separator are important parts of the design for the ejector-driven hydrogen circulation system. In this study, a novel ejector with water separation functionality is proposed based on a three-dimensional fluid transient simulation, which integrates the ejection and water separation functions in the traditional anode hydrogen circulation system. The separation efficiency of the novel ejector reaches 70.07% and 72.59% under low and high power, respectively, and the deviation is only about 3.47%. In addition, the entrainment ratios of 30 kW, 40 kW, and 50 kW have been improved by 12.54%, 8.04%, and 9.53%, respectively, through further optimization of the new ejector. The new ejector greatly simplifies the system structure while maintaining the original performance, which is innovative and beneficial to improving the power and energy density of the system.