Energy consumption analysis of heavy-duty vehicles for transient emissions evaluation on chassis dynamometer

Abstract

In order to acquire vehicle emissions and fuel economy by driving a vehicle on a chassis dynamometer, it is imperative that the chassis dynamometer should exactly simulate the road experience of the vehicle. In this paper, the modelling of a heavy-duty vehicle energy consumption both on the road and on a chassis dynamometer was developed and implemented by using two driving cycles. Road coast-down tests of a vehicle were conducted to obtain a road load equation of the vehicle. Its companion chassis dynamometer coast-down tests were aimed to estimate the characteristics of the dynamometer-vehicle system. Power absorber settings were achieved that duplicate the vehicle road load in the dynamometer testing. Comparing the measured energy of the vehicle between driving cycles on the chassis dynamometer and the calculated energy on the road, it is shown that the West Virginia University (WVU) transportable heavy-duty chassis dynamometer is successful in simulating the vehicle road load conditions when conducting emissions testing.

Development of an Emissions Monitoring Methodology Using On-Board NOx Sensors and Revision to Current In-Use Emissions Regulatory Protocols

“…The coast-down procedure is well defined and performed based on SAE J1263 suggested road load determination [67]. The coast-down fundamentals match the vehicle theoretical on-road coast-down time and the time taken for cost-down on the chassis dynamometer [68].…”