小型柔性接头缠裹式防热套力矩特性数值分析

Numerical analysis of wrapped boot torque characteristics of miniature flexible joint

为研究柔性接头缠裹式防热套的力矩特性,设计了带缠裹式防热套的小型柔性接头,弹性件和防热套材料均采用硅橡胶,分别建立带防热套和不带防热套的接头三维有限元模型,利用"二阶四项式"超弹本构模型表征硅橡胶材料的本构关系,数值模拟柔性接头在不同容压下的摆动过程,二者相减得到防热套力矩。在此基础上,研究了防热套剖面上的剪应力场分布及数值随容压的变化。为验证模型的准确性,将仿真的防热套力矩结果与试验值进行对比。结果表明,仿真与试验结果吻合较好,防热套力矩随容压的增加呈减小趋势,其原因是由于防热套剖面上的剪应力场分布变化引起的。

To investigate the wrapped boot torque characteristic of miniature flexible joint, a miniature flexible joint with silicone rubber elastomer and wrapped boot was designed. The 3D finite element models of flexible joint with boot and without boot were set up respectively.The second order invariant model was used to describe the constitutive relationship of the silicone rubber. The stress of the flexible joint with boot and without boot under different pressure with the same deflection angle was computed.The boot torque was obtained by subtracting the torque of flexible joint without boot from the total system torque. In addition, the shear stress on the boot under different pressure was analyzed. In order to verify the validity of the model, the simulation and experimental results of the boot torque under different pressure were compared. Results show that the simulation boot torque has a good agreement with the ex periment data.Boot torque decreases with enhancing pressure and it is caused by the shear stress of the boot section.