高压水介质往复密封接触特性有限元分析

Finite Element Analysis of Contact Characteristics of Reciprocating Seal Structure Under High-pressure Water Medium

对高压水介质往复滑动密封的密封特性进行分析。基于ANSYS/LS-DYNA软件建立U型橡胶往复滑动密封结构的有限元模型,确定Mooney-Rivlin橡胶材料模型和广义拉格朗日乘子接触算法,实现往复密封结构的三维非线性接触动力学仿真,并分析水介质压力、滑动杆运动方向及速度、接触摩擦因数等因素对密封特性的影响。结果表明:往复密封结构的应力集中于密封圈的沟槽、内唇口及底孔周边,滑动杆正向运动时速度和摩擦因数对密封接触特性的影响不大,而反向运动速度对密封接触应力的影响显著,密封失效发生在此阶段。

The characteristics of reciprocating sliding seal structure under high-pressure water medium were analyzed. The finite element model of U-ring reciprocating sliding seal structure was established based on ANSYS/LS-DYNA software, Mooney-Rivlin model was selected to characterize the hyperelastic rubber, and the Generalized Lagrange Multiplier Method was used as contact algorithm. The simulation of three-dimensional nonlinear contact dynamics of the reciprocating seal structure under different conditions was realized. The effect on sealing characteristics by the main factors such as water medium pressure, moving speed and the direction of sliding rod and contact friction coefficient for was analyzed. The resuits show that the ring groove, the inner lip and the circle of bottom hole are the main sites of contact stress concentrated on. When the slider moving forward, the velocity and friction coefficient have little effect on seal contact characteristics, while the reverse velocity has large effect on sealing contact stress, the seal failure may occur in this stage.