"基于Matlab的高效凸轮优化设计方法研究"

摘要 配气机构是内燃机的重要组成部分，而配气凸轮则是决定配气机构工作性能的关键零件。如何设计和加工出具有合理曲线的凸轮是整个配气系统设计中的关键问题。本文首先对凸轮进行分段设计，然后利用最大速度和最大加速度位置基于高次方程的凸轮运动规律进行设计优化，通过Matlab软件进行凸轮型线的优化设计。根据摇臂比计算气门的运动规律，然后通过变换摇臂比来反求凸轮的运动规律。借鉴高次方程凸轮设计经验，提出了一种新的凸轮设计方法，对气门运动规律进行了优化设计。将新设计的凸轮型线与原始凸轮型线进行对比，分析了新设计在升程、速度和加速度方面的改进。据此得出新设计对配气机构乃至整车所带来的影响。 关键词：凸轮；高次方程；变摇臂比；优化设计 Abstract The valvetrain is an important component of internal combustion engines, and the camshaft is a key component that determines the performance of the valvetrain. Designing and machining a camshaft with a reasonable cam profile is a critical issue in the overall valvetrain system design. This paper first divides the camshaft into segments and then optimizes the cam profile based on the motion law of the camshaft using high-order equations for maximum velocity and maximum acceleration positions. The cam profile optimization design is carried out using Matlab software. The motion law of the valve is calculated based on the rocker arm ratio, and the motion law of the camshaft is obtained by varying the rocker arm ratio. Drawing on the experience of designing high-order equation cams, a new method of camshaft design is proposed, and the motion law of the valve is optimized. A comparison is made between the new camshaft profile design and the original camshaft profile to analyze the improvements in lift, velocity, and acceleration achieved by the new design. Based on this analysis, the impact of the new design on the valvetrain and even the entire vehicle is discussed. Keywords: camshaft; high-order equations; rocker arm ratio; optimization design