Investigation of Heavy-Duty Vehicle Chassis Dynamometer Fuel Consumption and CO2 Emissions Based on a Binning-Reconstruction Model Using Real-Road Data

Abstract

Global warming is directly related to heavy-duty vehicle fuel consumption and greenhouse gas (CO2 mainly) emissions, which, in China, are certified on the vehicle chassis dynamometer. Currently, vast amounts of vehicle real-road data from the portable emission measurement system (PEMS) and remote monitoring are being collected worldwide. In this study, a binning-reconstruction calculation model is proposed, to predict the chassis dynamometer fuel consumption and CO2 emissions with real-road data, regardless of operating conditions. The model is validated against chassis dynamometer and PEMS test results, and remote monitoring data. Furthermore, based on the proposed model, the fuel consumption levels of 1408 heavy-duty vehicles in China are analyzed, to evaluate the challenge to meet the upcoming China fourth stage fuel consumption limits. For accumulated fuel consumption based on the on-board diagnostic (OBD) data stream, a predictive relative error less than 5% is expected for the present model. For bag sampling results, the proposed model’s accuracy is expected to be within 10%. The average relative errors between the average fuel consumption and the China fourth stage limits are about 3%, 8%, and 0.7%, for current trucks, tractors, and dump trucks, respectively. The urban operating condition, with lower vehicle speeds, is the main challenge for fuel consumption optimization.

Study on the Emission Characteristics of Typical City Buses under Actual Road Conditions

“…For instance, Guo Jiadong and others [10][11][12] utilized PEMSs to conduct on-road emission tests for Beijing China V stage diesel and natural gas vehicles, finding that natural gas vehicles have higher exhaust temperatures and can effectively reduce NOx emissions after installing SCR systems. Yang Qiang, Zhou Hua, and others [13][14][15][16][17] used OBD (On-Board Diagnostic) remote communication technology to analyze the operation and NOx emission characteristics of 11 hybrid buses with SCR systems, revealing that the hybrid buses operate in internal combustion engine mode for 32.4 ± 4% of the time, and NOx emissions increase by around 70% in winter compared to autumn. PEMSs have been widely used in several studies to test real-world on-road pollutant emissions from diesel-and CNG-fueled heavy-duty vehicles [18][19][20][21][22][23].…”