振动筛橡胶弹簧非线性刚度实验及仿真研究

Experiment and Simulation Research on Nonlinear Stiffness of Vibrating Screen Rubber Spring

采用实验方法及仿真计算,对振动筛用橡胶弹簧的非线性刚度特性进行研究.实验得到橡胶弹簧在压缩变形过程中刚度变化曲线,分析表明刚度变化可以划分为近似线性区和非线性区两个区间,通过最小二乘法拟合得到不同区间内橡胶弹簧刚度—压缩变形关系式;在实验数据基础上,应用应变能理论,建立了橡胶弹簧的非线性本构方程及其非线性有限元分析模型,很好地模拟了橡胶弹簧的整个压缩变形过程,模型有足够的精度.对于橡胶弹簧工作在近似线性刚度区的情况,提出了均值刚度的概念及其计算方法,建立线性有限元模型进行仿真分析,结果表明在近似线性刚度范围内能够较好地符合实验数据,可以作为非线性分析的替代,解决了非线性分析收敛困难的问题,并减少计算资源占用.本文的研究为振动筛用橡胶弹簧的设计和生产提供了分析方法和理论依据.

The nonlinear stiffness characteristic of vibrating screen rubber spring was researched by experimental analysis and simulation. The stiffness curves of rubber spring in the compressed deformation process were got by experiment. The results show that the stiffness variation of rubber spring can be divided into approximate linear region and nonlinear region. The relational expression is obtained by least square fitting for rubber spring stiffness - deformation in different regions. The nonlinear constitutive equation and nonlinear finite element model of rubber spring were built based on experimental data and strain energy theory. Nonlinear simulation results accord with the whole compressed deformation process, so the nonlinear model has sufficient precision. For the rubber spring working in approximate linear stiffness region, the concept of mean stiffness was proposed and the linear finite element model was built. The simulation accords with the experimental data better in the approximate linear region, so the linear model can be used as an alternative to nonlinear analysis in the approximate linear region. It makes the nonconvergence problem avoided, and the computing resource is reduced. The research provides analytical method and theoretical basis for design and produce of vibrating screen rubber spring.