A Study On The Influence Of 6105QB DI Diesel Engine's Operating Parameters On Smoke Emission And Noise Level

With 61 O5QB DI diesel engine machine for experiment as the study object, the thesis makes a research on the influence of five operation parameters (fuel angular advance, fuel injection pressure, valve clearance, rotation speed, load rate) on the smoke emission, noise level, power and fuel consumption rate of 6105QB DI diesel engine and proposes the method of optimizing the match of diesel engine operating parameters.Firstly, according to National Standard GB3847-93 Measuring Method of Full Load rate Smoke Emission ofAutomobile Diesel Engine, GB3846-93 Measuring Method of Free Accelerate Smoke Emission of Diesel Oil Vehicle and GB1859-89 Measuring Method of Diesel Engine Noise, on the basis of orthogonal experimental design, the influence of the three operating parameters (fuel injection pressure, fuel angular advance, valve clearance) on full-load smoke emission, free-accelerating smoke emission and noise level of diesel engine have been studied.Secondly, on the basis of orthogonal regression experimental design, the influence law of the five parameters (fuel angular advance, fuel injection pressure, valve clearance, speed, load) on smoke emission, noise level, power and oil consumption rate has been studied, and four regression equations including smoke emission, noise level, power rate, and fuel consumption rate equations concerning five operating parameters have been established. It has been proved that the regression equations have quite high accuracy and can be applied inprediction research. With the help of the four regression equations of smoke emission, noise level, power and fuel consumption rate, multi-aim optimizing design has been adopted to optimize the match of three operating parameters (fuel angular advance, injection pressure and valve clearance), so as to improve the comprehensive performance of the diesel engine, and the optimized results are very prominent.The results of the study reveal that the influence of the five operating parameters on smoke emission, noise level is correlative instead of being independent. Generally speaking the increase of fuel angular advance leads to the decrease of smoke emission value, while the increase of load rate of speed may lead to fast increase of noise level, as a result the emphasis of noise reduction should be put on the condition of high load rate and rotation speed. The influence of fuel injection pressure on smoke emission value is comparatively complicated, while its influence on noise level is comparatively small. When the valve clearance increases, smoke emission increases too, but its influence on noise level is not very prominent. Appropriate match on parameters is an important requirement for the diesel engine to keep a comparatively high comprehensive performance, so excessive maintenance and good technique condition of diesel engine is an important way to reduce the smoke emission, noise level, and improve the performance of the engine.