Design of an Active Vapor Recovery System and Simulation Analysis of Refueling Characteristics Under Refueling Conditions for Plug-in Hybrid Electric Vehicles

When plug-in hybrid electric vehicles operate under electric motor drive conditions for extended periods, the vapor recovery technology in traditional fuel system fails to meet vapor emission requirements. Therefore, research into new vapor recovery technologies is essential. Based on the vapor recovery technology of traditional fuel systems, a novel active vapor recovery system for vehicle fuel systems was designed. A simplified simulation model of the active vapor recovery system was constructed, and the refueling characteristics were analyzed from two aspects: the formation of oil seals during refueling and the smoothness of refueling process. The results indicate that the refueling flow rate and the diameter of the refueling pipe are important factors affecting the refueling characteristics, and the formation time of the oil seal can be shortened by increasing the refueling flow rate or reducing the diameter of the refueling pipe. However, to ensure a smooth refueling process, excessively large or small flow rates and pipe diameters should be avoided. This study provides valuable design directions, methods, and recommendations for the development of new vapor recovery systems.