带卸压槽的微摩擦气缸Fluent仿真分析

针对超低频模态测试悬挂系统中微摩擦气缸抗侧向能力不足的问题,提出一种在活塞尾部增加环形卸压槽的新结构。建立了活塞外表面与气缸内表面之间气膜流场特征参数的仿真模型,并进行Fluent仿真计算,结果表明,增加环形卸压槽改善了气膜的气压分布，在两排节流孔之间形成了具有一定宽度且稳定的承载区，使活塞的轴线与气缸的轴线基本保持平行，提高了抗侧向能力及气膜刚度，从而使气缸工作更为稳定。试验结果进一步验证了仿真结果，证明带环形卸压槽的微摩擦气缸的性能得到了提高。

Analyses on a New Type of Tiny Friction Pneumatic Cylinder with Pressure Relief Groove

For overcoming the deficiencies of former tiny friction pneumatic cylinder applied in a passive zero-spring-rate suspension system, a new type of tiny friction pneumatic cylinder with pressure relief groove was putted forward. A Fluent simulation model of gaseous film between the surface of the piston and the cylinder tube was established. The conclusion after simulation by  Fluent demonstrates the new one with groove has more reasonable pressure distribution. The area between two rows of flow restriction orifice has more regular and stable bearing capacity. That makes axis of the piston parallel with the axis of the cylinder tube. And by physical experiments,the simulation conclusion has been confirmed that the new one with groove has better stability and better ability to bear lateral force.