直列六缸发动机激振力分析与仿真

Analyzing and simulation of exciting forces of L6 engine

为了高效且准确地分析发动机的激振力,建立了发动机7自由度振动模型.根据激振源和激振作用的不同,把发动机的激振力分为了4类:惯性激振力、惯性驱动力矩、缸压激振力、缸压驱动力矩,并建立了单缸模型,分别给出数学表达式.从单缸激振力出发,根据各缸的相位差推导出多缸发动机的激振力.针对某排量为6.75L的直列六缸发动机,仿真得出其激振力变化.

In order to analyze the exciting forces of engine effectively and accurately,the engine vibration model with seven degree of freedom(DOF)is established and the exciting forces are categorized into four types according to their exciting sources and objects:inertia exciting force,inertia driving torque,cylinder pressure exciting force,cylinder pressure driving torque.The model of single cylinder is established and the mathematical expressions are given.According to the single cylinder exciting force and the phase difference between each cylinder,the mathematical expressions of exciting force of multi-cylinder engine are deduced.The simulation of a 6.75 L-displacement L6 engine shows the characteristic of its exciting force.