基于Abaqus的悬架空气弹簧静态力学特性研究

以某商用车悬架用空气弹簧为研究对象,应用非线性有限元分析软件Abaqus建立了空气弹簧的有限元分析模型,对其垂向静态力学特性进行了计算分析,并与悬架空气弹簧垂向静态力学特性台架试验结果进行对比.结果表明,仿真计算结果与试验结果吻合度较好,证明数值仿真方法可用于悬架空气弹簧设计开发.     

膜式空气弹簧力学特性有限元分析

膜式空气弹簧作为空气悬架的关键部件,其刚度特性已经成为决定汽车性能的关键因素之一。通过非线性有限元软件ABAQUS对其刚度特性及影响因素进行分析,在仿真过程中选择Mooney-Rivlin模型作为橡胶材料的超弹性本构模型,采用ABAQUS中的Rebar单元进行帘线层的模拟,对气体和囊壁之间的气固耦合进行了详细的模拟分析。在考虑了非线性和接触问题后,建立了空气弹簧的三维非线性有限元模型。最后,通过分别改变对空气弹簧特性影响较大的初始内压、帘线层数和帘线层间距三个方面对弹簧的刚度特性进行了研究,结果为空气弹簧在帘线层方面的设计与优化提供了参考。     

基于变帘线参数的商用车膜式空气弹簧刚度特性研究

运用非线性有限元分析软件Abaqus建立膜式空气弹簧有限元模型,对其刚度特性进行仿真模拟分析,讨论帘线角、帘布层间距、帘布层数和帘线密度等橡胶气囊帘线参数对空气弹簧垂直和横向刚度特性的影响。结果表明,膜式空气弹簧刚度随着帘线角和帘布层数增大、帘布层间距减小而提高,而帘线密度的影响很小。有限元分析结果与试验数据之间的误差不超过5%,证明该模型是有效的。     

APDL实现空气弹簧动态试验仿真

介绍了EQ6111空气弹簧的试验方法和结构材料特点，并针对性地在ANSYS中建立了空气弹簧的三维有限元模型。针对空气弹簧分析过程中所存在的气压载荷问题，采取多步分析的思路，基于离散求和法APDL编写胶囊容积计算宏，应用于空气弹簧的垂向和横向动态力学性能分析，得出了位移载荷频率分别为0．5Hz，1Hz，2Hz和2．5Hz下的横向和垂向动态力学性能分析结果。研究表明，载荷频率是影响空气弹簧动态力学性能的关键外在因素之一。本文的研究为更进一步的空气弹簧动态力学性能的有限元分析奠定了基础。     

膜式空气弹簧刚度特性影响因素研究

介绍空气弹簧刚度特性的影响因素,并利用有限元分析软件ABAQUS建立膜式空气弹簧有限元模型,分析气压对空气弹簧刚度特性的影响。结果表明,气压是影响膜式空气弹簧刚度特性的重要因素,随着气压的提高,弹簧的垂向和横向承载能力均增大。     

初始内压和帘线间距对膜式空气弹簧横向刚度特性影响的有限元分析

运用ABAQUS分析软件建立膜式空气弹簧的有限元模型,通过仿真计算获得负荷-横向位移曲线,研究初始内压和帘线间距对膜式空气弹簧横向刚度的影响。结果表明,空气弹簧的横向刚度随着初始内压的提高而增大,同时由于空气弹簧膨胀造成帘线间距增大,引起横向刚度降低。本研究为膜式空气弹簧设计中合理选择初始内压和帘线间距提供了参考。     

汽车悬架空气弹簧静态力学性能有限元建模与计算

以一款膜式橡胶空气弹簧作为研究对象,进行了三维建模和静态力学特性有限元分析,并与实验测试结果对比,验证了采用有限元软件对空气弹簧的建模与力学性能计算结果的准确性与可行性。文中的有限元建模和计算方法对空气弹簧力学性能计算分析与优化设计具有一定的指导意义。     

基于Abaqus的汽车用空气弹簧的有限元分析及试验研究

采用非线性有限元分析软件Abaqus建立汽车用空气弹簧的模型,并对其垂向特性进行模拟分析。结果表明：空气弹簧的垂向载荷随充气压力的增大呈线性增大,定值充气压力下随帘线角度的增大而减小;最大外直径和最大应力随帘线角度的减小而增大;垂向静刚度随充气压力的增大而呈线性增大,随帘线角度的增大而减小,定值充气压力下随工作高度的增大先减小后增大,存在一最小刚度。试验验证了有限元分析结果的正确性。     

商用车膜式空气弹簧静刚度的有限元分析

以商用车底盘用膜式空气弹簧（简称膜式空气弹簧）为研究对象,对其静刚度进行有限元分析,并与试验结果进行对比。结果表明：采用流体腔法表征气囊内腔气体压力更符合膜式空气弹簧的实际工作过程;采用膜单元法和嵌入单元法对膜式空气弹簧气囊囊皮进行建模,对其静刚度曲线的整体趋势影响很小,但在大行程工况下静刚度存在差异;为了更好地反映气囊囊皮结构对膜式空气弹簧静刚度的影响,推荐采用流体腔法和嵌入单元法进行膜式空气弹簧静刚度仿真。     

空气弹簧有限元仿真方法的研究

介绍空气弹簧有限元仿真步骤,对螺钉紧固式和自密封式空气弹簧进行仿真模拟,并进行试验对比。利用螺钉紧固式空气弹簧仿真模型计算了胶囊的性能;利用自密封式空气弹簧仿真模型计算了整个空气弹簧(胶囊和辅助弹簧)的性能,包括胶囊气腔和附加气室在不同气体交换粘度下的空气弹簧载荷-气压关系、垂向刚度和横向刚度,据此提出空气弹簧的仿真模拟方案:先根据少量试验数据对比垂向刚度结果,优化出符合真实条件的空气弹簧系统的粘性特征,在此粘性条件下计算其他工况下空气弹簧的性能参数。     

基于流固耦合的带附加气室空气弹簧的力学特性研究

应用流固耦合和有限元理论,通过ABAQUS软件仿真分析附加气室容积和节流口直径变化对带附加气室空气弹簧弹性力学特性的影响.结果表明:在一定范围内附加气室容积和节流口直径变化对空气弹簧的垂直刚度有明显的影响.     

Multistep analysis of the mechanical performance of an air spring

New methods for testing air springs have received a lot of interest in recent years. In this article APDL (ANSYS parametric design language) was utilized to simulate static and dynamic test process of air springs. In the simulation, multiple load steps solution was carried out through APDL *DO‐LOOP and array parameter method. The program (capsule volume calculating macro) based on scatter sum method enabled the loop. The scalar quantity PRESSURE was established as inner tracking parameter to update inner pressure. Table parameter PRESSURES was established as inner pressure output parameter to export inner pressure of each load step. According to rubber elastic behavior and cord‐rubber composite aeolotropy, hyper elastic element and layer element were preferred for simulation. Comparison was done between static simulation results and corresponding test data to prove feasibility of multistep analysis. In consequence, some major parameters such as cord angle, initial inner pressure, and auxiliary chamber volume were taken into account, which have remarkable effect on static mechanical performance of EQ6111 air spring. Finally, the same method was applied to the simulation of dynamic test process, achieving abundant analysis results according to every 0.5 Hz increment of load frequencies varying from 0.5 to 2.5 Hz. Load frequency threw remarkable effect on the dynamic mechanical performance of EQ6111 air spring, because inertial effect and damping effect played important roles therein. The study aims to make contribution to the development of platform of air spring simulation and parameterized design (PASSPD). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

油封唇口压力大小及分布的有限元分析

利用ANSYS建立了橡胶油封的2维轴对称模型,分析了过盈量、唇口接触宽度R,弹簧劲度以及后唇角β与油封唇口压力大小及分布的关系。分析结果验证了前人在油封设计及应用选型方面经验的正确性。该分析方法在油封设计及选型方面将起到一定的指导意义。这些分析为油封的构型优化奠定了基础。     

MODELING VACUUM-CONTACT DRYING OF WOOD: THE WATER POTENTIAL APPROACH

A two-dimensional mathematical model for vacuum-contact drying of wood is presented. The moisture and heat equations are based on the water potential concept whereas the pressure equation is formulated considering unsteady state conservation equation of dry air. Most of the model parameters were determined during independent experiments. The set of equations is then solved in a coupled form using the finite element method. The validation of the model is performed using experimental results obtained during vacuum-contact drying of sugar maple sapwood. The experimental and calculated data are in good agreement. Nevertheless, some discrepancies are observed which can be attributed to the boundary conditions used and to the fact that heat transfer by convection was neglected.     

MODELING VACUUM-CONTACT DRYING OF WOOD: THE WATER POTENTIAL APPROACH

ABSTRACT

A two-dimensional mathematical model for vacuum-contact drying of wood is presented. The moisture and heat equations are based on the water potential concept whereas the pressure equation is formulated considering unsteady state conservation equation of dry air. Most of the model parameters were determined during independent experiments. The set of equations is then solved in a coupled form using the finite element method. The validation of the model is performed using experimental results obtained during vacuum-contact drying of sugar maple sapwood. The experimental and calculated data are in good agreement. Nevertheless, some discrepancies are observed which can be attributed to the boundary conditions used and to the fact that heat transfer by convection was neglected.     

NONLINEAR PI CONTROLLER FOR pH PROCESS

The control of pH is one of the most difficult challenges in the process industry because of the severe nonlinearities and high precision required in manipulating the flow rate. The Wiener model, which consists of a linear dynamic element followed by a nonlinear static element, is used for representing such nonlinear processes. Piecewise continuous polynomials are used for mapping the nonlinear static gain accurately. A nonlinear PI controller was designed based on the Wiener model. Simulation results on the nonlinear mathematical model are presented to highlight the superior performance of the Wiener model based nonlinear PI controller in comparison to that of the local linear PI controller. The performance of the nonlinear PI controller was further improved upon by using the method of inequalities to obtain a single set of PI controller settings that takes into account the parametric variations in the linear dynamic element at different operating points. Simulation and experimental results are presented to support the work.     

NONLINEAR PI CONTROLLER FOR pH PROCESS

The control of pH is one of the most difficult challenges in the process industry because of the severe nonlinearities and high precision required in manipulating the flow rate. The Wiener model, which consists of a linear dynamic element followed by a nonlinear static element, is used for representing such nonlinear processes. Piecewise continuous polynomials are used for mapping the nonlinear static gain accurately. A nonlinear PI controller was designed based on the Wiener model. Simulation results on the nonlinear mathematical model are presented to highlight the superior performance of the Wiener model based nonlinear PI controller in comparison to that of the local linear PI controller. The performance of the nonlinear PI controller was further improved upon by using the method of inequalities to obtain a single set of PI controller settings that takes into account the parametric variations in the linear dynamic element at different operating points. Simulation and experimental results are presented to support the work.