不等深螺旋槽干气密封性能的研究

Study on the Performance of Dry Gas Seal with Cone-shaped and Ladder-like Spiral Groove

为进一步提高螺旋槽干气密封的密封性能,对螺旋槽的结构做创新性的优化,保持坝区和堰区不变,只改变螺旋槽底部形态,将等深螺旋槽改进成收敛型不等深螺旋槽。通过建立有限元模型,用Matlab软件编程求解出气膜压力分布,对比分析等深槽、收敛型阶梯不等深槽、收敛型锥度不等深槽、发散型阶梯不等深槽和发散型锥面不等深槽5种槽型的密封性能参数。对比分析收敛型阶梯不等深槽不同锥度下的密封参数。结果表明,收敛型阶梯不等深螺旋槽与收敛型锥度不等深螺旋槽具有十分相似的密封性能,但收敛型阶梯不等深螺旋槽具有更好的泄漏量稳定性,且更易加工;0.04°收敛型阶梯不等深螺旋槽干气密封的密封性能最优越,控制泄漏量方面更为突出,并可获得较好的推开效果。

The structure of spiral groove was innovatively optimized to improve the sealing performance of spiral groove dry gas seal, with keeping the dam zone and weir zone still, changing the bottom shape of spiral groove only, substituting the different deep groove for the equal deep groove. Gas blanket pressure distribution was solved with Matlab software by building up finite element model. Five kinds of groove types were analyzed, namely equal deep groove, convergent ladderlike different deep groove, convergent tapering different deep groove, divergent ladder-like different deep groove and divergent tapering different deep groove. The sealing parameters of convergent ladder-like different deep groove with different angles were contrastively analyzed. The results show that the sealing performance of convergent ladder-like different deep spiral groove dry gas seal is parallel to the one of convergent tapering different deep groove. But the anterior one shows more stability in leakage rate control and more ease in manufacture. The convergent ladder-like different deep groove with 0.04 degrade angle is the most superior at controlling leakage rate and helping to open the sealing faces.