高温高压和高速工况下SCO_(2)动压密封端面的热弹变形研究  

Thermoelastic deformation of SCO_(2)dynamic pressure seal faceunder high temperature,high pressure and high speed

作　　者：陈坤毅 马润梅[1] 廖浩然 施任杰 程天馥 李双喜[1] CHEN Kun-yi;MA Run-mei;LIAO Hao-ran;SHI Ren-jie;CHENG Tian-fu;LI Shuang-xi(School of Mechanical and Electrical Engineering,Beijing University of Chemical Technology,Beijing 100029,China)

机构地区：[1]北京化工大学机电工程学院,北京100029

出　　处：《机电工程》2021年第4期405-412,共8页Journal of Mechanical & Electrical Engineering

基　　金：国家重点研发计划资助项目(2018YFB2000800);中央高校基本科研业务费专项资金资助项目(BHYC1703A)。

摘　　要：在高参数工况下,超临界二氧化碳(以下简称SCO_(2))动压密封的端面容易发生热弹变形,从而影响动压密封性能,针对该问题,建立了SCO_(2)动压密封热流固耦合数值分析模型。在考虑了粘性耗散的基础上,求解了密封环温度场,采用CO_(2)真实物性数据求解了流体膜压力场,将温度场和流体膜压耦合到密封环上,求解了密封端面的热弹变形;对比研究了热变形和弹变形对热弹总变形的影响,分析了转速、压力和温度对密封端面热弹变形的影响规律,提出了减少热弹变形的方法。研究结果表明:SCO_(2)在动压密封高温下宜减小密封环的温差,以减小端面变形,高压下宜采用高弹性模量材料以减小端面变形,高转速下依靠动环热变形与弹性变形互相抑制关系以减小端面热弹总变形;密封环的端面最大轴向间隙与介质温度呈线性关系增大,与压力呈线性关系减小;转速则使其先减小,后增大。Aiming at the problem that the sealing end face of SCO_(2)dynamic pressure seal was prone to undergo thermoelastic deformation under high-parameter working conditions,which affected the sealing performance,a thermo-fluid-solid coupling numerical analysis model of SCO_(2)dynamic pressure seal was established.The temperature field of the seal ring was solved by considering the viscosity dissipation.The real physical property data of CO_(2)was used to solve the fluid film pressure field.The temperature field and fluid film pressure were coupled to the seal ring to solve the thermoelastic deformation.The effects of thermal deformation and elastic deformation on the total thermoelastic deformation were studied and compared,the influence of speed,pressure and temperature on the thermoelastic deformation of the sealing end face was analyzed,and a method to reduce the thermoelastic deformation was proposed.The results indicate that SCO_(2)dynamic pressure seal should reduce the temperature difference of the seal ring at high temperature to reduce the deformation of the end face.High elastic modulus materials should be used to reduce the end face deformation under high pressure.At high speed,the total thermal elastic deformation of the end face can be reduced relying on the mutual restraint relationship between thermal deformation and elastic deformation of the moving ring.The maximum axial clearance of the end face of the seal ring increases linearly with the medium temperature,and decreases linearly with the pressure.The speed makes it first decrease and then increase.

关 键 词：超临界二氧化碳 动压密封 热弹变形 高参数工况 

分 类 号：TH136[机械工程—机械制造及自动化] TB42[一般工业技术]