The Effect of Speed and Acceleration on Emission Ratio Based on Actual Road Driving: A Case of Xiaodian District in Taiyuan

Abstract

To support scientific management strategy for reducing transportation gas emission, this study investigates the emission principles of different exhaust gases (CO, HC, NOX) in different driving states. The OBEAS-3000 vehicle exhaust gas detector was used to collect the instantaneous emission rate of motor vehicle exhaust at different speeds and accelerations in field experiments. Based on the data, the effects of speed and acceleration rate on the emission rate of different exhaust gases by partial correlation methods were analyzed. Results show that there are potential interactions between acceleration and velocity effects at different gas emission rates and emission ratios. At different stages of the velocity and acceleration, the proportions of CO and HC emissions are significantly different, but the proportion of NOX changes little. At the low-velocity stage, emission ratios of CO and HC have no significant changes in different acceleration stages. In the mid-speed driving phase, the CO emission ratio is positively correlated with the acceleration, whereas the HC emission ratio is negatively correlated with the acceleration. During the high-velocity driving period, CO and HC emission ratios have no significant change in different acceleration stages. The results provide theoretical supports for establishing accurate emission models for various gases.