The Study Of Performance Influence Based On Heavy-duty Diesel Engine With Bio-diesel Blended Fuel

Bio-diesel fuel,one of clear and re-new source,has tremendous potential to solve severe oil safety and environment pollution problems.Its combustion characteristic can reduce effectively emissions and environmental pollution.So,the research on the biodiesel fuel can seek an effective method reducing energy consumption and combustion emission and it has realistic guiding significance.The main contents are as following:Firstly,two methods including bench test and simulation are used and the performance of the engine burned with same pure diesel fuel is compared between bench test and simulation.The deviation has been controlled in valid engineering scope and the accuracy and reliability of the simulation model are verified.Then,the fuels from different volume rate of bio-diesel including 0%、10%、20%、50%、100%(B0、B10、B20、B50、B100)has been carried out physics-chemistry properties test to perfect the bio-diesel fuel databases and to finish the simulation model.The simulation calculation is based on five different blended bio-diesel fuel and 8 kinds of cases involving two kinds of speed of 1950 r/min and 2100 r/min and 4 kinds of load characteristics.The different fuels effect on combustion characteristic,power,fuel consumption and emission have been analyzed.The research result shows that the power of the diesel engine declines slightly,fuel consumption increases using bio-diesel fuel.With the increase of biodiesel blending ratio,soot and THC reduces gradually,and NOx eventually increases.The blending 5 kinds of biodiesel effect on the engine performance has been analyzed comprehensively.The result indicates that using B20 is more effective than other bio-diesel fuel.Lastly,the fuel economy and emission performance of the diesel engine have been optimized based on B20 by the method of changing pre-injection mass and boost pressure.The Latin hypercube sampling algorithm to design experiment method referred to the 8 kinds of cases of European steady-state cycle including low 、middle speed and low、 middle 、high and all load has been used.The simulation of the each sample point is calculated.The model between test factor and response variables has been built and the optimization based on the model has been finished.The optimization result shows: At average,NOx has decreased 17.2%,fuel consumption rate has decreased 4.2%,and soot has increased slightly.But the soot is far behind with the level burned B0.In the paper,the simulation analysis based on five kinds of different bio-diesel can reveal that the bio-diesel fuel has bright future as one of liquid substituted fuel and optimized project in the research becomes reference foundation for developing engine burned biodiesel fuel in the future.