动力总成磁流变悬置的动态特性分析

以某动力总成悬置为研究对象建立力学模型,推导出磁流变悬置在低频工况和高频工况下动刚度与阻尼角的表达式,运用Matlab软件对磁流变悬置的动态特性进行仿真,并进行了试验验证。通过仿真分析了磁流变悬置的橡胶主簧等效面积、阻尼可控通道的长度、磁流变悬置的上液室体积柔度、磁流变液零场粘度等结构参数的变化对悬置动态特性的影响,为磁流变悬置的设计提供参考。     

流动模式磁流变悬置动态特性分析

针对某型号发动机,基于低频大刚度大阻尼的理想悬置特性要求,提出了一种新型流动模式磁流变悬置,采用ANSYS对磁流变悬置的核心结构进行磁场有限元分析,确保磁路设计的合理性。为研究流动模式磁流变悬置在低频大振幅激振时的动态特性,建立了磁流变悬置的集总参数模型,利用MATLAB分析许用激励电流范围内的动态特性,克服以往仅对几个离散激励电流点的动刚度及阻尼滞后角进行分析的不足,为磁流变悬置的智能隔振控制奠定了基础,具有重要的工程应用价值。     

汽车动力总成磁流变悬置的磁路模拟分析与试验验证

根据磁流变液的流变特性设计了一种新型半主动磁流变悬置结构,并简述了该悬置结构和工作原理。利用ANSYS电磁场分析模块对悬置结构内部磁场进行了有限元分析,研究了相同磁流变液悬置结构下,不同隔板材料对磁流变液悬置磁场分布的影响,并分别测试了采用不同隔板材料时磁流变液悬置的动特性。结果表明,所选择的低磁导率铝合金隔板材料可改善悬置性能;在磁流变悬置的设计过程中引入ANSYS的电磁场分析方法可行并具有一定的通用性。     

基于磁流变悬置的整车建模与振动控制的研究

以磁流变悬置动态性能试验结果为数据样本,利用广义回归神经网络(GRNN)辨识方法建立了磁流变悬置的正、逆模型,并将辨识模型用于悬置系统的控制;建立了基于磁流变悬置的整车10自由度动力学模型,以发动机转速和悬置点处的加速度信号为输入,设计了模糊控制器,对磁流变悬置进行半主动控制的仿真。结果表明:该模糊控制器具有较好的宽频隔振效果,悬置点处的振动加速度峰值明显减小,验证了GRNN模型和模糊控制器算法的正确性和有效性。     

电流变液力发动机悬置动态特性研究分析

对电流变液力发动机悬置的结构及工作原理进行了描述,建立了该悬置的力学及数学模型,并利用ADAMS软件对其动态特性进行了仿真研究。通过试验测试了电流变液力悬置的动态特性,并将仿真结果与试验结果进行了比较分析。对比分析结果表明,仿真结果与试验结果比较吻合,从而验证了模型的实用性和可信性。     

动力总成半主动悬置动态特性仿真与试验研究

分析了某轿车动力总成半主动悬置的结构及工作原理,应用键合图理论建立了该悬置系统键合图模型和数学模型,并进行了系统动态特性仿真计算。仿真结果与台架试验结果对比表明,悬置在低频段仿真与试验结果具有良好的一致性,验证了采用键合图方法研究悬置低频动态特性的适用性和可信性。该研究可为半主动悬置结构设计及动态特性仿真分析提供参考。     

汽车液压悬置系统动态特性研究

液压悬置是一种先进的减振系统,其动态特性对汽车的乘坐舒适性和NVH性能有很人影响。但是液压悬置的动态特性非常复杂,既具有频变特性,又具有非线性特性。本文基于系统辨识及数值分析理论,提出了模拟液压悬置动态特性的一种数值拟合方法。     

汽车液压置系统动态特性研究

液压悬置是一种先进的减振系统，其动态特性对汽车的乘坐舒适性和NVH性能有很大影响。但是液压悬置的动态特性非常复杂，既具有频变特性，又具有非线性特性。本文基于系统辨识及数值分析理论，提出了模拟液压悬置动态特性的一种数值拟合方法。     

汽车动力总成液压悬置参数试验研究

对汽车动力总成的空气弹簧式液压悬置进行受力分析,建立动力学模型,通过一系列试验获取悬置的参数,并利用它们对动力学模型进行仿真,得到空气弹簧式液压悬置的动态特性,并与试验得到的动态特性做比对。结果表明,空气弹簧式液压悬置仿真与试验的动态特性基本一致,说明所建立的仿真模型是正确的,所获取的液压悬置参数是准确的。     

基于NSGA-Ⅱ算法的磁流变悬置磁路多目标优化

以磁流变悬置的磁路体积最小、输出阻尼力最大为优化目标,基于ANSYS参数化设计语言(APDL)建立了磁流变悬置磁路结构的多目标优化模型,采用带精英策略的快速非支配排序遗传算法(NSGA-II)进行优化,获得了磁路结构的Pareto最优解,并采用模糊集合理论对Pareto最优解进行选优。根据优化前后的磁路结构尺寸加工了两个磁流变悬置,并对悬置动态性能进行试验。结果表明:所提出的磁流变悬置磁路多目标优化方法是正确有效的,能够获得更加紧凑的磁流变悬置磁路结构,并提高悬置的输出阻尼力。     

On the Design and Development of a Magneto-Rheological Mount

This paper evaluates the performance of a Magneto-Rheological (MR) mount. The mount incorporates MR fluid in a conventional fluid mount to open and close an inertia track between the fluid chambers of the mount. It is shown that such switching of the inertia track improves the mount's isolation effect by eliminating the large transmissibility peak that commonly exists at frequencies larger than the notch frequency for conventional fluid mounts. The switching frequencies of the MR mount are evaluated based on the parameters of the mount. A simple control scheme for switching the mount between the open and closed states is proposed, and the performance of the controlled mount is compared with conventional mounts. A sensitivity analysis is conducted to evaluate the effect of parameter errors in estimating the switching frequencies and mount performance. The results show that the switching frequencies can be accurately determined from mount parameters that are easily measured or estimated.     

On the Design and Development of a Magneto-Rheological Mount

This paper evaluates the performance of a Magneto-Rheological (MR) mount. The mount incorporates MR fluid in a conventional fluid mount to open and close an inertia track between the fluid chambers of the mount. It is shown that such switching of the inertia track improves the mount's isolation effect by eliminating the large transmissibility peak that commonly exists at frequencies larger than the notch frequency for conventional fluid mounts. The switching frequencies of the MR mount are evaluated based on the parameters of the mount. A simple control scheme for switching the mount between the open and closed states is proposed, and the performance of the controlled mount is compared with conventional mounts. A sensitivity analysis is conducted to evaluate the effect of parameter errors in estimating the switching frequencies and mount performance. The results show that the switching frequencies can be accurately determined from mount parameters that are easily measured or estimated.     

Semi-active engine mount design using auxiliary magneto-rheological fluid compliance chamber

Engine mounts are used in the automotive industry to isolate engine and chassis by reducing the noise and vibration imposed from one to the other. This paper describes modelling, simulation and design of a semi-active engine mount that is designed specifically to address the complicated vibration pattern of variable displacement engines (VDE). The ideal isolation for VDE requires the stiffness to be switchable upon cylinder activation/deactivation operating modes. In order to have a modular design, the same hydraulic engine mount components are maintained and a novel auxiliary magneto-rheological (MR) fluid chamber is developed and retrofitted inside the pumping chamber. The new compliance chamber is a controllable pressure regulator, which can effectively alter the dynamic performance of the mount. Switching between different modes happens by turning the electrical current to the MR chamber magnetic coil on and off. A model has been developed for the passive hydraulic mount and then it is extended to include the MR auxiliary chamber as well. A proof-of-concept prototype of the design has been fabricated which validates the mathematical model. The results demonstrate unique capability of the developed semi-active mount to be used for VDE application.     

发动机主动悬置3种控制方法的比较

应用LMS自适应前馈控制、LQR控制和模糊PID控制3种方法对发动机电磁式主动悬置进行研究.在MATLAB/Simulink环境下建立了主动悬置控制系统模型,并以车身垂向加速度为性能指标进行了仿真分析,对比了采用上述3种控制方法时主动悬置的隔振能力、鲁棒性和稳定性.仿真结果表明,在主动悬置的控制上模糊PID控制方法优于其他两种控制方法.     

某车型后减振器上支座失效分析优化

针对某车型整车道路试验过程中出现的后减振器上支座失效问题,通过查看分析故障件的失效状态,结合应用Abaqus软件进行CAE仿真分析,确定了其失效的主要原因是由于在整车运动过程中,上支座衬套的橡胶凸台的应力太大。对此提出了改进的设计方案,通过台架试验和整车道路试验的验证,结果表明,改进后的后减振器上支座解决了耐久失效问题,同时经整车NVH和操稳性能评价后确认改进方案未对整车性能产生不利影响。     

汽车发动机磁流变悬置隔振效果试验评估

在采用四端参数法对加速度振级落差模型进行理论推导及分析的基础上,提出了以可测量、易操作的加速度振级落差对悬置系统的隔振效果进行试验评估。汽车发动机分别采用橡胶悬置及磁流变悬置,对采集得到的动态激振力数据进行了自功率谱函数估计,对振动加速度数据进行了频谱分析,并根据加速度频谱中二阶主频处的数据对悬置系统进行了评估。结果显示,磁流变悬置不仅被动隔振效果的评估结果优于橡胶悬置,而且发动机低速段采用较大电流、高速段采用小电流的控制策略使得隔振效果更好。     

基于流固耦合有限元法的汽车发动机液力悬置动力学分析

介绍了车载发动机液力悬置流固耦合的有限元分析法,模拟了液力悬置的动态响应。通过瞬态时域响应的模拟结果,计算了液力悬置的动态性能。在计算过程中使用ALE方法进行坐标变换,有效解决了流体力学和结构动力学在坐标系上的不一致问题。计算过程无须估算或测试液力悬置的流体阻尼,无须测量橡胶主簧的体积刚度,可以得到液力悬置在时域内的动态响应,仿真结果与试验测试结果吻合较好。     

Vibration Control of a Passenger Vehicle Utilizing a Semi-Active ER Engine Mount

This paper presents vibration control of a passenger vehicle using an electronically controllable electro-rheological (ER) engine mount. A mixed-mode ER engine mount operating under the flow and shear modes is devised and manufactured. After establishing the dynamic model of the proposed ER engine mount, both field-dependent displacement transmissibility and dynamic stiffness of the ER engine mount are empirically evaluated. The ER engine mount is then incorporated with a full-vehicle model in order to investigate vibration control performance at the driver's seat position. The governing equation of motion of the full-vehicle model is formulated by considering engine excitation force, followed by designing a skyhook controller to attenuate unwanted vibration. The controller is implemented through a hardware-in-the-loop simulation (HILS), and control responses such as acceleration level at idle speed are evaluated in the frequency and time domains.     

Vibration Control of a Passenger Vehicle Utilizing a Semi-Active ER Engine Mount

This paper presents vibration control of a passenger vehicle using an electronically controllable electro-rheological (ER) engine mount. A mixed-mode ER engine mount operating under the flow and shear modes is devised and manufactured. After establishing the dynamic model of the proposed ER engine mount, both field-dependent displacement transmissibility and dynamic stiffness of the ER engine mount are empirically evaluated. The ER engine mount is then incorporated with a full-vehicle model in order to investigate vibration control performance at the driver's seat position. The governing equation of motion of the full-vehicle model is formulated by considering engine excitation force, followed by designing a skyhook controller to attenuate unwanted vibration. The controller is implemented through a hardware-in-the-loop simulation (HILS), and control responses such as acceleration level at idle speed are evaluated in the frequency and time domains.