中文摘要：

针对某型号的柴油发动机,利用matlab软件的数据处理功能和绘图功能,对柴油发动机试验数据采用最小二乘法和多元线性回归的方法进行拟合处理,通过对比不同拟合阶数所得拟合结果,根据评判标准,选取最理想的拟合曲线方程,建立发动机的数学模型。所建模型具有较高的精度,发动机的外特性和万有特性曲线清楚地表达发动机的性能。对发动机的特性曲线进行分析,得出发动机的动力性能指标和经济性能指标随转速变化的规律,以及最大功率、最大转矩和最低燃油消耗率所对应的转速,同时也得到发动机的最佳经济性和最佳动力性曲线,为研究发动机与无级变速器之间的匹配问题提供理论和技术基础。

英文摘要：

For a certain type of diesel engine,it is used that the methods of least square fitting and multiple linear regression surface fitting to process the test data of the engine based on the data processing and drawing function of matlab software in this paper.The fitting results are different because of different fitting orders.According to the judgment standard,it is selected that the optimal fitting equation,and the mathematical model of the engine is established,which has high accuracy.The characteristics of the engine can be described clearly by the external characteristic and universal characteristic curve.By analyzing the characteristics curve of the engine,It can be seen the change trend of the main characteristic parameters of engine such as torque,power and fuel consumption rate.The corresponding speed under the condition of the maximum output power,maximum torque and minimum fuel consumption rate can be got.And the optimal economic and power performance curve of engine can be obtained.It provides the important theoretical and technical foundation of studying the matching method of continuously variable transmission and engine.