密封间隙力对泵转子临界转速的影响分析

随着给水泵的大功率化、高转速化的发展,为保证多级离心泵转子部件的平稳运转,避免其在接近其临界转速时产生共振,需要对设计中的转子进行干态、湿态下的临界转速计算.论文以5级离心给水泵为主要模型,采用有限元法分别计算其在干态、湿态下的临界转速,通过对比,得出密封间隙力对转子临界转速的影响.干态情况下,分别用邓克莱法和有限元法计算给水泵的一阶临界转速;湿态情况下,分别计算密封设计间隙及二倍间隙不同情况下的临界转速,对比结果,表明密封间隙力对泵转子临界转速的影响非常大,并且与密封间隙的大小密切相关.

Analysis on the Influence of the Critical Speed for the Forces in Annular Seals

The power and speed of the pump rotor is higher and higher, to ensure the stable running of the multistage centrifugal pump rotors and avoid resonance, how to calculate accurately in dry critical speed and wet critical speed is very important. In this paper ,the main model is based on a five stages pump rotor, using FEM to calculate the critical speed in dry and wet state. Comparing the result, we can gain the influence of the critical speed for the forces in annular seals. In dry state, using Dunkerley Method and FEM to calculate the critical speed; in wet state, calculate the critical speed on seal clearance of first and twice time, the result show that the forces in annular seals makes a large influence to the critical speed, and relates to the seal clearance.