Study On Emission Measurement Technologies Of Heavy-Duty Diesel Vehicle Based On Test Bench

Heavy-duty diesel vehicle is the main tool for goods exchange and public transportation. With increasing of economic activities, developing of municipal construction, and expanding of public transportation network, the existing number of heavy-duty diesel vehicle becomes much bigger. Currently, emission test for heavy-duty diesel vehicle can be implemented both on heavy-duty chassis dynamometer and engine test bench. However, emission test prescibed by low, for heavy-duty diesel vehicle, can only be carried out on engine test bench.In this study, the factors, which influence test results during emission test on engine test bench for heavy-duty diesel vehicle, were investigated, including control parameter settings of test bench control system and sampling parameter settings of emission test system. This work helped to enhance the standardization and consistency of law-required emission test.The components and number of particulate matter(PM) discharged from diesel engine were studied. The test for PM components can help to control the emission of PM. The test for PM number is required by EuroⅥemission regulations in the future. In this study, PM number emission tests were carried out on two diesel engines, which meet the EuroⅢand EuroⅣemission regulations, respectively. Some characteristics for PM number emission were obtained.Compared with previous regulations, EuroⅥemission regulations for heavy-duty diesel vehicle have changed a lot. In this study, the main changes were described detailedly. Furthermore, a diesel engine, which meets the EuroⅥemission regulations, was tested on current bench to investigate the requirements for ultra-low emission measurement.On Board Diagnostic(OBD) system was required for EuroⅣand latter stages. In this study, the general requirements and test method for OBD system, which defined by China’s regulations, were introduced detailedly.In summary, the emission measurement technologies for heavy-duty diesel vehicle based on test bench were studied comprehensively.