【作者】 刘建霞；

【导师】 黄大明； 韦志康；

【作者基本信息】 广西大学 ， 农业机械化工程， 2004， 硕士

【摘要】 本文在现有柴油／乙醇双燃料发动机研究的基础上，针对柴油／乙醇预混合存在的掺烧比不能随发动机工况实时改变的不足，结合现有的试验条件，采用乙醇进气管喷射的方法，利用传感器、数据采集卡和虚拟仪器软件进一步改进并完善乙醇喷射的电子控制系统。并在此基础上，进行电控系统优化的试验研究：改变发动机的结构参数(供油提前角)和乙醇的喷射时刻，同时综合考虑柴油、乙醇的混合比例，进行双燃料发动机性能试验，寻找双燃料发动机动力性、经济性和烟度最优工况点的发动机供油提前角和乙醇喷射时刻。 本试验研究的电控系统由传感器和LabVIEW虚拟仪器软件组成，借助PCI-6024E数据采集卡，信号调理电路，并结合软件编程，达到柴油／乙醇混合比例随发动机工况的变化而实时改变的目的。乙醇喷射时刻的确定是通过发动机一缸进气门的气门升程对应曲轴转过的角度来确定，并借助传感器接收乙醇喷射时刻信号盘的触发信号，促使计算机发出一串喷醇脉冲信号，该信号的长度是计算机根据掺烧比和检测到的柴油量计算产生的，可以实现对乙醇掺烧比随发动机工况改变的实时控制。 通过三个供油提前角、四个供醇时刻组合的全因素试验，比较双燃料发动机与原机相同工况下的性能发现：双燃料发动机的动力性、经济性和烟度与原机相比均有不同程度的改善；在最佳供油提前角，以有效功率、当量燃油消耗率、烟度为实验指标，供醇时刻、转速、负荷率为因子，进行无交互作用的正交试验，分别建立有效功率、当量燃油消耗率、烟度与供醇时刻、转速、负荷率的二次回归正交多项式数学模型。以上结论将对以后的深入研究起到一定的借鉴指导作用。更多还原

【Abstract】 In this thesis, a new method is adopted that the ethanol sprays is installed in the intake pipe of the diesel. But the existing research on the oil/ethanol double fuel is mixed before, and the mix proportion can not be changed with the engine operating mode. Using the new method, combining the existing experimental condition, utilizing sensor, data collecting card and virtual instrument, the electronic controlled system of the ethanol sprayed can be improved and perfected. Further more, taking advantage of the electronic control system, an optimal experimental study is carried on the oil/ethanol double fuel engine: Changing structure parameter of engine (the angle of the oil spray) and ethanol spray time, considering the mixed proportion of the diesel and ethanol, looking for optimum engine operating mode of the double fuel engine in which its strength, economy and smoke degrees are all better.The electronic controlled system of this experimental study is made up of hardware-the sensor and software-Lab VIEW, which are connected by PCI-6024E data collecting card. The signal transition circuit and the program help change the mixed proportion of the diesel and ethanol in time with the operating mode of the engine. Ethanol spray time is the bent angle corresponding the valve tappet’s position of the first cylinder, which will be sure by the ethanol spray signal coming from sensor touched by the signal dish fixed on the oil pump. The signal dish impels the computer to produce a string of pulse of ethanol spray, the length of pulse is calculated by computer according to the mix proportion and the oil of diesel. The electronic control system can change the mix proportion frequently with the operating mode ofthe engine.The whole factor experiment is formed by three angles of oil spray and four ethanol spray time. Comparing the result between the original diesel and the double fuel engine at the same operating mode, the conclusion can be drawn that power, equivalent rate and smoke of the double fuel engine are all better than the original diesel’s; In the best angle of oil spray, regard effective power, equivalent oil consumption rate, smoke as the experiment index, ethanol spray time, rev, load rate as factors, the orthogonal regression experiment is carried on, based on the experiment, three regression equations about effective power, equivalent oil consumption rate, smoke degree has been set up. The optimal operating mode of the engine has been found. The above-mentioned conclusions will be reference in the later deep research.更多还原