小锥度环形密封转子动特性  

Dynamic coefficients of small cone-shaped annular seal rotor

作　　者：王乐勤[1] 周文杰[1] 邢桂坤 姚德群[2] 翟璐璐[1] 吴大转[1] 

机构地区：[1]浙江大学化工机械研究所,浙江杭州310027 [2]中国寰球工程公司,北京100029

出　　处：《排灌机械工程学报》2013年第6期517-522,539,共7页Journal of Drainage and Irrigation Machinery Engineering

基　　金：中国石油天然气集团公司工程建设分公司科学研究与技术开发项目(60030)

摘　　要：为求解小锥度下液体环形密封动特性系数和转子所受激振力的大小,建立了小锥度环形密封全三维模型,利用CFDFluent软件及其气穴模型计算得到了转子表面压力分布和气穴存在的位置.研究了进出口压差、ω/Ω和不同转速下小锥度环形密封转子表面压力变化规律,并得到了不同转速下气相分布情况.最后依据转子动力学模型和激振力方程,分析了压差分别为1.38,2.41,3.45MPa和转速分别为1.02×104,1.74×104,2.46×104r/min情况下密封动特性系数和涡动比.将计算值同Childs的理论值和Lindsey的试验值进行了对比.结果表明:增加进出口压差、增大ω/Ω和提高转速均能增大小锥度环形间隙压力,有效减小气穴范围,提高环形间隙密封性.模拟结果同试验值和理论值基本吻合,并且整体上更接近于试验值,这为具有小角度液体环形密封的工程研究提供了理论依据.To solve the liquid dynamic coefficients of small cone-shaped annular seal and exciting force that rotor sustained,a full three-dimensional model of small cone-shaped annular seal was built.By applying CFD Fluent software to cavitation model,the surface pressure distribution of rotor and location of cavitation were obtained.The rotor surface pressure variation under the condition of pressure drop,ω/Ω and different rotor speed were studied,and the distribution of the gas phase was obtained.Finally,as per rotor dynamic model and excitation force formulas,seal dynamic coefficients and whirl-frequency ratio were analyzed under conditions of pressure drop 1.38,2.41 and 3.45 MPa;rotor speed 1.02×104,1.74×104 and 2.46×104 r/min respectively.Calculated values were then compared with theoretical values of Childs and experimental values of Lindsey.The results show that,by increasing the pressure drop,the ω/Ω or speeding up the rotor,small cone-shaped annular seal gap pressure can be increased,cavitation range can be reduced effectively and the sealing performance of annular seal can be improved.The simulation results correspond closely to experimental values and theoretical va-lues,wholly approaching the experimental values.The research can provide theoretical basis for engineering study of small cone-shaped liquid annular seal.

关 键 词：转子 动特性系数 小锥度 环形密封 涡动比 

分 类 号：S277.9[农业科学—农业水土工程] TB42[农业科学—农业工程]