The focus of this research is to develop the optimum design of torsional vibration damper using hybrid damping approach to decrease the torsional vibrations in the cranktrain system of internal combustion engines (ICE). For this purpose, a double mass rubber and viscous torsional vibration damper (DMRV-TVD) are combined. The optimization procedure is carried out using genetic algorithm (GA) to determine the best hybrid damping performance on cranktrain system of a four stroke and four cylinder diesel engine. Accordingly, twelve degrees of freedom lumped mass mathematical model of the proposed cranktrain system is created. The stiffness and damping coefficients of viscous and rubber materials used in DMRV-TVD model are verified by modal test and finite element natural frequency analysis. Then, the excitation torque is calculated considering the inertia forces and gas force, and Fourier series expansion is performed to obtain the harmonics of driven torque as the input load on the relevant masses. The relative angular deflection of the front end point of the crankshaft is determined. Additionally, in order to decrease the torsional vibrations of the crankshaft, DMRV-TVD model is optimized depending on the viscous material parameters by defining the boundary conditions and objective function of the genetic algorithm. The comparative results show that the developed hybrid design of optimized DMRV-TVD reduced the torsional vibrations by 50.17% when compared to the non-optimized DMRV-TVD. This achieved reduction in the torsional vibrations is expected to increase the engine performance and its durability as well as providing a better driving comfort and fuel efficiency.

这项研究的重点是使用混合阻尼方法来开发扭振减振器的优化设计，以减少内燃机曲轴系统（ICE）的扭振。为此，将双重质量的橡胶和粘性扭转减振器（DMRV-TVD）组合在一起。优化过程是使用遗传算法（GA）进行的，以确定四冲程四缸柴油机曲轴系统上的最佳混合阻尼性能。因此，创建了所提出的曲轴系统的十二个自由度集总质量数学模型。通过模态试验和有限元固有频率分析，验证了DMRV-TVD模型中使用的粘性和橡胶材料的刚度和阻尼系数。然后，在考虑惯性力和气体力的情况下计算出励磁转矩，并进行傅立叶级数展开，以获得驱动转矩的谐波作为相关质量上的输入负载。确定曲轴前端点的相对角偏转。另外，为了减少曲轴的扭转振动，通过定义遗传算法的边界条件和目标函数，根据粘性材料参数优化了DMRV-TVD模型。比较结果表明，与未优化的DMRV-TVD相比，优化的DMRV-TVD的混合设计可将扭转振动降低50.17％。