2缸发动机平衡机理研究及悬置系统优化设计

摘要

Taking a 2-cylinder engine as an object,the motion law of piston-crank mechanism was analyzed and the unbalanced forces and moments under actual operating condition were deduced.Then the balance method of rotating and reciprocating iner-tia forces for the 2-cylinder engine was researched and the impacts under different balance conditions were simulated.Moreo-ver,the optimized model of mounting system for the 2-cyliner engine was built and the optimization of natural frequency,ener-gy decoupling rate and mount dynamic reaction force were carried out with the sequence quadratic programming (SQP)method. The optimization of mounting system for the 2-cylinder engine shows that the method can reduce the engine excitation trans-ferred to vehicle body effectively.%以2缸发动机为研究对象，分析发动机曲柄活塞机构的运动规律，推导发动机在实际工作时产生的不平衡激励力和力矩，研究2缸发动机的旋转惯性力和往复惯性力的平衡方法，对一台2缸发动机在不同平衡条件下产生的激励进行数值模拟。在此基础上，建立2缸发动机悬置系统优化模型，以悬置系统的固有频率、能量解耦率和悬置动反力为优化目标，用序列二次规划法进行多目标的优化，对一台2缸柴油机进行了悬置系统优化设计。分析结果表明该优化方法可以有效减少发动机传递给车身的激励。