车载加油油气回收装置加油特性试验

Refueling Experiment of On-board Refueling Vapor Recovery

针对装有车载加油油气回收装置(On-board Refueling Vapor Recovery,ORVR)的汽车燃油蒸发污染物控制系统,在分析加油过程蒸发排放影响因素的基础上,按照ORVR加油试验的规范,进行燃油温度、环境温度和加油流量等因素对加油蒸发排放影响的试验;通过测量加油管内油液压力的变化来反映液封状态,分析加油管管径和加油流量对液封形成的影响规律,讨论减少加油蒸发排放的可能途径,并提出促进液封改善的措施。研究中把加油过程划分成三阶段:液封作用段、排放增长段与加油跳枪段,着重分析各个因素对液封作用段和排放增长段的影响。研究结果表明:燃油温度主要对排放增长段的影响较大,而环境温度则与之相反;加油流量不能过高,也不能过低;加油管内径的大小与加油流量会影响加油管内液封形成时间,安装阻流环能够促进大管径加油时的液封形成;研究结果可为ORVR的设计提供相关参考。

In allusion to the automobile evaporative emission control system with the on-board refueling vapor recovery （ORVR） apparatus, experiments on the influence of fuel temperature, ambient temperature and filling flow on refueling evaporative emission were conducted, based on the refueling experiment criterion of ORVR and the analysis of influencing factors of refueling evaporative emission. The influence of filling pipe diameter and filling flow on liquid seal was discussed with experiments, whilst the liquid seal status was reflected by means of measuring pressure of fluid in the filling pipe. It was necessary to reduce the refueling evaporative emission and propose the approaches to promoting the liquid seal. The refueling process was divided into three stages, namely, liquid seal stage, emission growth stage and the shut-off and refueling stage. Then the analysis focuses on the influence of various factors on liquid seal stage, emission growth stage. The results show that the fuel temperature mainly influences the emission growth stage hut the ambient temperature has little effect on emission growth stage. The test suggests that refueling flow should not be too high or too low. It is obvious that filling pipe diameter size and refueling flow can affect formation time of the liquid seal, and the restrictive ring can accelerate the speed of the liquid seal formation. The results provide references for the design of ORVR.