The Performance Analysis Of The Middle-duty Truck Matching Based On High Pressure Injection Diesel Engine

With the development of transportation and automobile industry, the truck industry also develop quickly, the number of it is growing rapidly and which has being become the fundamental mode which plays an important role in the economy growth of China. With the increase of the vehicle population and the extensive use of the truck, more and more fuel is consumed, so our country becomes a big importer. At the same time, the automobile performance required is much higher than before, especially for the considering of the fuel economy and dynamic, so it is importantly how to fulfill the best compatible between engine and chassis to make the automobile own better ability and the excellent emission.For the performance of the vehicle, the extent of the power-transmission matched with the engine has a major influence on the drive ability, economical and emission performance. The middle-duty truck is a kind of transport, which is required a better economical and freight cutting based on the drive ability, and also meets emission standards of country. Making the engine often works in the ideal and economical region, it can not only improve the fuel economy performance, reduce the engine abrasion, enhance the engine use life, but also improve the emission performance.Constantly updated of the emulation software, the emulation results is more accurate than before, the method of vehicle matching usually adopts emulation software to prediction, then matching vehicle again base on the emulation results. To assure the great precision of the model, we use software of GT-SUITE which developed by CD-adapco Company in Japan, the liability and accuracy of the computation result is assured for all the models have been calibrated according to the experiment date. GT-DRIVE is used for establishing the entire vehicle model, simulation results are various performance indicators. Using GT-POWER completely established the model of the diesel engine. The paper also introduces the main functions:application range and specific operation process of GT-DRIVE and GT-POWER, and introduces the part model too. GT-DRIVE is used for performance of entire vehicle, and the model is studied on the drive ability, economical and emission performance. Using GT-POWER completely established the model of the diesel engine, which studied impact of the injection pressure and injection timing on engine performance, then summarized a brief analysis of the emission characteristics.The important content of this paper are as follows:(1) For a middle-duty truck bases on fixed power-transmission, comparative analysis vehicle performance which hich is matched monomer pump engine instead of high pressure common rail. Due to the six working cycle can better response the actual operating conditions, so the method of simulation adopts six working cycle, drawing engine performance and the power curve of a million plans compares different dynamic, economy and emission characteristics in simulation process, formulating appropriate shift rule, ensure dynamic and fuel economy of the whole vehicle.(2) Matching high pressure common rail engines, inprovements is not obviously in NOX emissions, so adjusting the parameters of fuel injection system, analysis influence of engine performance for injection pressure and injection timing, and optimizing frequently-used area to minimize NOX emissions, ensure dynamic and fuel economy of the whole vehicle also.(3) Because of the middle-duty truck is modified by special vehicle, top speed is lower than similar models, so the truck need to calculation of vehicle chassis parameters and matching the transmission system again.The results of the study indicate that:keeping chassis parameters constant monomer pump engine instead of the high pressure common rail vehicle engine, economic performance has improved greatly, and in six working cycle of HC and CO emissions performance have improved a lot but NOX.We can improve it through adjusting injection pressure or injection timing. Remin the same engine and recalculated chassis parameters, the economic performance of vehicle are improved, the top speed has greatly ascend, emission also improved. Overall, the purpose of comparison and analysis for vehicle matching is achieved.