超高速干气密封微织构气膜润滑特性研究

Study on lubrication characteristics of micro-textured gas film in ultra-high speed dry gas seal

针对航天航空领域,设备超高速、高压运转,干气密封稳定性问题,依据槽型织构优化设计,提出一种槽底微织构螺旋槽干气密封结构,以解决密封在超高速旋转过程中气膜稳定性问题。基于气体润滑理论,建模、划分网格,再导入FLUENT软件对流场进行仿真模拟;改变工况参数和槽型结构参数后,在超高速、高压工况下,相比于普通螺旋槽,槽底微织构螺旋槽干气密封的动压效果有显著提升。结果表明,槽深h_(g)=6μm,膜厚h_(0)=2μm,微织构槽深δ=2μm、微织构槽宽取3.97 mm,微织构槽位于螺旋槽底中间位置时,槽底微织构螺旋槽相比于普通螺旋槽可产生明显的动压效应。

In response to the problems of ultra-high speed,high-pressure operation,dry gas seal stability of equipment in the aerospace field,based on the optimized design of groove texture,a dry gas seal structure with micro-textured spiral groove at the bottom of the groove was proposed to solve the problem of the stability of the gas film in the process of ultra-high-speed rotation of the seal.Based on the theory of gas lubrication,a model was built,mesh division was carried out,and then imported into Fluent to simulate the flow field;after changing the working condition parameters and the parameters of the groove structure,compared with the ordinary spiral groove under the high pressure and ultra-high speed conditions,the dynamic pressure effect of spiral groove dry gas seal with micro-texture at groove bottom was significantly improved.The results show that when the groove depth h_(g)=6μm,film thickness h_(0)=2μm,microtextured groove depthδ=2μm,microtextured groove width 3.97 mm,and microtextured groove is located in the middle of the bottom of the spiral groove,the microtextured spiral groove at the bottom of the groove can produce a significant dynamic pressure effect compared with the ordinary spiral groove.