Search Results

This research aims at establishing a procedure to simulate the fuel consumption and CO2 emissions of a CNG-powered vehicle from real-world mass emission measurement data. In order not to be dependant on characteristic maps derived from test bed measurements a procedure to define an analytic function which describes the fuel consumption of the whole powertrain from real-world onboard emission measurements has been developed. This procedure involves developing a closed loop simulation program in Matlab/Simulink for driving resistances, driver behavior, powertrain and vehicle. The simulation program calculates the fuel consumption and CO2 emissions with around ±3% accuracy compared with real-world measurements when the vehicle is driven on significantly different types of urban routes.

An optimized monofuel CNG light duty vehicle based on the Opel Zafira was investigated under real-world conditions and the results are presented in this study. To analyze the real-world performance of the monofuel CNG vehicle due to fuel consumption and exhaust emissions representative experimental test on road-test routes were performed, including sections with significantly different driving conditions. Furthermore, driving tests at different constant speeds on freeway were carried out. A benchmarking to the same vehicle with diesel powertrain was done as well. The test vehicles were equipped with a new compact on-board measurement system and additionally GPS tracking to link the received geographic information of the road-test routes with the measured exhaust mass emission data. The measurement results were validated with Matlab Simulink models of the powertrain and vehicle.