具有单向离合解耦器的发动机前端附件驱动系统的旋转振动建模及参数优化设计

建立了具有单向离合解耦器(Overrunning Alternator Decoupler,OAD)的八轮-多楔带发动机前端附件驱动系统的非线性旋转振动数学模型.采用Gear数值算法求解从动轮和张紧臂的角度波动.计算结果表明,有OAD装置时从动轮和张紧臂的角度波动、各带段的动态张力和带-轮间的滑移率等系统动态特性均明显减小.计算和研究了OAD弹簧刚度的大小、电机转子与电机轮惯量比的大小以及电机负载转矩的大小对系统动态特性的影响.以张紧臂角度波动、OAD弹簧转矩和带-电机轮间的滑移率最小为优化目标,建立了OAD弹簧刚度和电机转子转动惯量两参数的优化设计数学模型.结果表明,采用优化后的系统参数,该系统的动态特性均得到一定程度的改善.

Rotational Vibration Modeling and Parameters Optimization Design of Engine Front End Accessory Drive System with Overrunning Alternator Decoupler

A mathematical model for nonlinear rotational vibration analysis of an eight pulley-belt engine front end accessory drive system(FEADs)equipped with an overrunning alternator decoupler(OAD)is established.Gear’s method is used to calculate the angle fluctuations of driven pulleys and tensioner arm.Calculation results show that the dynamic characteristics of the FEADs including angle fluctuations of driven pulleys and tensioner arm,tension of each belt span,and slip ratio between belt and pulley decrease remarkably with an OAD equipped.The dynamic properties of the FEADs are investigated with different spring stiffness of the OAD,different inertia ratio between alternator rotor and pulley,and different external loading on alternator.Optimization design model of two parameters including spring stiffness of the OAD,and inertia of alternator rotor is established.Minimum of angle fluctuation of tensioner arm,spring torque of the OAD,and slip ratio between belt and alternator pulley are taken as objective functions.Optimization parameters are obtained by using Fminimax function in the Matlab software.Analytical results show that the dynamic responses of the FEADs decrease significantly after parameter optimization.The modeling,calculation and optimization design for a FEADs equipped with an OAD,are instructive for the rotational vibration control of a serpentine belt accessory drive system.