发动机减压缓速器在商用车上的应用研究

Research on Application of Compression Release Engine Retarder in Commercial Vehicle

针对国内在用发动机制动技术效果不佳的问题,运用内燃机运动学和热力学理论,构建了发动机减压缓速器工作过程数学模型,采用MATLAB软件通过数值计算的方法模拟分析了发动机转速、减压气门提前开启角、开启速度及气门最大开度等相关参数对其工作性能的影响,确定最佳参数值,实现发动机减压缓速器工作性能的改善。运用试验对模型进行了验证,试验结果与模型计算结果吻合度高,证明模型准确可行。研究结果表明:发动机转速越高,减压缓速器制动能力越大;对应每一发动机转速都存在一个最佳气门提前开启角和最大开度,转速越高,最佳气门提前开启角和最大开度越大;发动机转速一定时,减压气门开启速度越快,减压缓速器制动能力越大。

To deal with the low braking capability of domestic braking technology, a mathematical model of the working process of compression release engine retarder was established with the theory of thermodynamics and kinematics of internal combustion engine, and a simulation analysis was made on the effect of related parameters （engine speed, compression release valve opening angle in advance, valve opening speed and maximum opening） on retarder performance using MATLAB software and numerical calculation to determine optimal parameters in order to improve the performance of engine compression release engine retarder. The model was verified with experiment, and the experimental results fitted the model calculation results, which proved the model is feasible. The research results show that the higher the engine speed, the greater the braking capability; there is an optimal valve opening angle in advance and a maximum opening at each engine speed, and the higher the speed, the greater the optimum valve opening angle in advance and the maximum opening; with engine speed being constant, the higher the opening speed of compression release valve, the greater the braking capability of compression release engine retarder.