PEMS-Based Multi-level Analysis of Fuel Consumption and Emissions for Heavy-Duty Diesel Vehicles

Real-World fuel consumption, emission and driving data from heavy-duty diesel vehicles (HDDVs) were collected using portable emission measurement system (PEMS). Then, the fuel consumption and emission characteristics were analyzed at microscopic, mesoscopic as well as macroscopic levels. The analysis results on driving behaviors showed that the driving time was mainly distributed in low and middle-speed bins, the driving distance was mainly located in middle-speed bins, and the driving time and distance under cruise mode accounted for the highest proportion. The analysis results on fuel consumption and emission characteristics showed that the average level of fuel consumption was 18.6 L/100 km, the average emission factors of NOx and PM were 4.63 g/km and 0.087 g/km for HDDVs, which met Euro III standard. At the microscopic level, driving at high-speed and acceleration is associated with the instantaneous high fuel consumption and emission rates. At the mesoscopic level, idling or driving at low-speed was the main reason of high fuel consumption and emission factors. At the macroscopic level, driving distance was a significant influencing factor for total fuel consumption and emissions calculation.