摘要
万有特性曲线是具有多参数的特性曲线,最内层的等燃油消耗率曲线是最经济的区域,耗油率最低。曲线愈向外,经济性愈差,从中很容易找出最经济的负荷和转速。利用Matlab软件,建立了发动机特性模型,绘制了发动机的万有特性曲线,以汽车原地起步换挡加速时间和等速行驶工况燃油消耗作为衡量动力性和燃油经济性的目标,分别建立动力性目标函数和经济性目标函数。采用线性加权组合的方法将两个分目标函数转换成单一目标函数。结果表明:采用Matlab软件进行优化计算,找到最优的加权因子即得到动力性与经济性的最佳优化匹配方案,曲线结果准确可靠。
Universal characteristic curve is a curve with several parameters. The inner layer of the fuel consumption rate curve is the most economic region and the lowest rate of fuel consumption,and the outer of the curve is the economy worse. By these curves,it is very easy to find the most economical load and speed. The traditional drawing method of universal characteristic is based on the load characteristic curve and the velocity curve,and is by hand. Hand drawing is time-consuming and laborious, coordinate the process of drawing calibration errors can occur but also has the disadvantages of large numbers of data etc. With the increase of speed and data processing ability of computer calculation,and the application of advanced computer programming,especially the application of scientific computing software Matlab language,drawing of possible universal characteristic curve can be completed automatically. Using Matlab software,the engine model is established in this paper and characteristic curve is drawn by the engine model. The time of vehicle starting to gearing up and the fuel consumption of constant speed are considered as two goals to measure the dynamic performance and fuel economy,dynamic objective function and economy objective function are then established. By using the method of linear weighted combination,the two objective function is converted into a single objective function. The result shows that the optimum calculation by Matlab software,finds the optimal weighting factors and obtains the best matching scheme optimization for power and economy of the curve. The result is accurate and reliable.
出处
《实验室研究与探索》
CAS
北大核心
2014年第3期33-36,75,共5页
Research and Exploration In Laboratory
基金
廊坊市科技局科技支撑计划课题(2011011041)
