Low Inertia Turbocharged Diesel Engine's Influence On The Performance Of Overload Highway Tractor Research

The vehicle energy saving has become an important research topic, and heavy-duty commercial vehicles which is an important component of energy-saving, accounted for 56.2% of car fuel consumption. The heavy duty commercial vehicles energy-saving work will be the key work content of each big diesel engine enterprise, and the international development trend of heavy-duty diesel engine is low speed and high torque. Therefore, In this paper, the low-speed performance and acceleration performance of a heavy duty diesel engine which match on Liuzhou Motor Co., M7 type “arrogant dragon” heavy duty truck were optimized, to improve torque at low engine speeds, reduce fuel consumption and shorten acceleration time.This paper studied the matching of turbocharger and the dragon heavy truck engine by using the method of combining experiment and simulation. The main work and results of this thesis are as follows:(1) This paper studied the matching of two different turbochargers and engine by using the calculation and experiment method. Experiment s showed that the engine with low-inertia turbocharger can obviously improve the engine performance under the engine speed of 1200 r/min, and the low-speed torque was improved, fuel consumption and smoke emission were reduced. Low-inertia turbocharger makes the engine speed which has the best fuel consumption lower than the original turbocharger. The engine speed which has the best fuel consumption is 1300r/min with the original turbocharger, and 1100r/min with the low-inertia turbocharger. Moreover, maching the Low-inertia turbocharger the best engine fuel consumption is improved 2g/k W·h than maching the original turbocharger.(2)A full vehicle model of the “arrogant dragon” heavy duty truck was built using AVL-CRUISE to simulate the truck's ordinary operat ing condition and to compare the experiments results with simulation findings. Simulation showed that the difference between the two turbochargers is the maximum at 70km/h vehicle speed with the top gear, which is a 1.24L/100 km lower fuel consumption obtai ned by the low-inertia turbocharger when compared with the original turbocharger. But the speed accelerating performance of the vehicle equipped with different turbocharger was not shown with significant difference.(3) In order to evaluate the performance of the vehicle equipped with different turbocharger, vehicle speed was fixed on 70km/h highway condition and at 50km/h on second grade highway conditions, where the experiments on highway condition show more broad guidance. Experiments showed that low-inertia turbocharger operated at maximum efficiency zone when vehicle speed is about 60-70km/h while engine speed is about 100-1200r/min. Therefore the engine fuel consumption with low-inertia turbocharger is significantly reduced by 1.88L/100 km than the orig inal engine, the extent about 5.0%. Correspondingly, the engine with low-inertia turbocharger also shows 1.1L/100km(the extent about 5.0%) lower fuel consumption on second grade highway. Experiments also show similar accelerating performance of the two vehicles.