| As the number of vehicles possessed is growing rapidly year by year, the fuel consumption of vehicles is also increasing year by year. The fuel flow meter measurement method is mainly used as current fuel consumption measurement of vehicles in China, but this fuel consumption detection method is not fit for fuel supply system and the injection system of vehicles adopting new technology, as well as the large semi-trailer and other vehicles for testing. Therefore, it is necessary to study the fuel consumption detection method of non-disassembly. In the vehicle performance testing station for rapid fuel consumption measurement, the key technology is the fuel consumption calculation model and the simulation of driving conditions, and these two aspects are mainly studied.With aspects of vehicles'technical performance, vehicles' weight, air resistance and road environment, the influential factors of the vehicle fuel consumption are analyzed in detail and make a conclusion that except for the technical condition of vehicles, the environmental factors such as resistance to the roads are also important to the influential factors of fuel consumption; through the analysis of the combustion theory, the fuel consumption test model of gasoline engine based on carbon balance is established, and on this basis, the test model used in the carbon-neutral diesel fuel is concluded, the three parameters of carbon balance model need to be calculated and the specific measurement method is given.The formation mechanism of resistance of the vehicles is analyzed, and three kinds of test methods for drag coefficient are analyzed. Based on that, the test method of the present study about a multi-speed glide is clarified, and the multi-speed glide resistance model is established. The loading principles of the chassis dynamometer is shown, namely:â‘ the setting of the chassis dynamometer is equal to the equivalent of the base vehicles'quality and the equivalent inertia of wheel driven;â‘¡chassis dynamometer power absorption unit is mainly used to simulate the air resistance of vehicles on the road and part of the rolling resistance of vehicles on the road, and its value should be equal to the difference of the road loading and the total friction loss between the system.Through the sliding test of seven buses and six trucks on the road, each vehicle's tire rolling resistance coefficient and their respective air drag coefficient are calculated using multi-speed slide method. Through the sliding test of chassis dynamometer HYCG-130LD6 and HYCG-100E1, two dynamometers' rig resistances are calculated by the method of the regression analysis. Vehicles with different tires slide on the chassis dynamometer tests, and different types of tire rolling resistance coefficient are measured. Compared with the vehicle rolling resistance coefficient on the road,that rig rolling resistance coefficient with the same kinds of tires is two times of the rolling resistance coefficient is concluded, and making use of the conclusions, tire rolling resistance coefficient on the road without the road sliding test is calculated. According to the distribution of tire model and road rolling resistance coefficient, the approximate values originates of different tire rolling resistance coefficient are got.The load force that the chassis dynamometer simulates road driving resistance and load force calculated accurately are comparatively analyzed, and the error between them is in the acceptable range.At last, the non-disassembly fuel consumption detection test based on the carbon balance method is verified, and the results show that on the different loading conditions of chassis dynamometer, the relative errors between the values of the constant speed fuel consumption testing method and the values of the carbon balance model testing method were less than 5%. So it shows that the present study based on carbon balance method of chassis dynamometer loading test system is practical, to meet needs of the vehicle inspection without disassembly fuel consumption.
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