含杂质CO_(2)干气密封运行工况点物性参数计算及密封温度场分析  

Calculation of Physical Parameters and Analysis of Temperature Fields of CO_(2) with Impurities Dry Gas Seal at Operating Points

作　　者：陈维 宋鹏云[2] 许恒杰[2] 孙雪剑 CHEN Wei;SONG Pengyun;XU Hengjie;SUN Xuejian(Faculty of Mechanical and Electrical Eng.,Kunming Univ.of Sci.and Technol.,Kunming 650500,China;Faculty of Chemical Eng.,Kunming Univ.of Sci.and Technol.,Kunming 650500,China)

机构地区：[1]昆明理工大学机电工程学院,云南昆明650500 [2]昆明理工大学化学工程学院,云南昆明650500

出　　处：《工程科学与技术》2023年第1期265-278,共14页Advanced Engineering Sciences

基　　金：国家自然科学基金项目(52105189);云南省基础研究专项青年项目(202101AU070019)。

摘　　要：在“碳达峰、碳中和”背景下,二氧化碳(CO_(2))捕集利用与封存(carbon capture, utilization and storage,CCUS)技术作为减少CO_(2)排放的最有效策略已成为世界关注的热点。针对应用于CCUS技术中的离心式压缩机,以螺旋槽干气密封为研究对象,含杂质CO_(2)为润滑介质,基于EOS–CG(equation of state for combustion gases and combustion gas-like mixtures)模型获得干气密封运行工况范围内含杂质CO_(2)混合物密度、焓值、声速及焦耳–汤姆逊系数等热力学参数;考虑实际气体效应、黏温压效应、阻塞流效应、离心惯性效应及润滑介质与密封端面间的对流换热,采用有限差分法耦合求解雷诺方程、能量方程及密封环热传导方程,获得含杂质CO_(2)干气密封压力场、温度场、开启力、泄漏率等稳态性能参数。结果表明:当温度一定时,密度随压力的增大而增大,焓值、焦耳–汤姆逊系数随压力的增大而减小;当压力一定时,密度随温度的增大而减小,焓值随温度的增大而增大,在较低压力区域,声速随温度的增大而增大,焦耳–汤姆逊系数随温度的增大而减小;当密封进口压力为12 MPa、进口温度为380 K、转速为15 000 r/min时,含杂质CO_(2)干气密封出口压力为1.9 MPa,气膜进出口温差约为23 K,密封环端面内外径温差约为10 K;以转速、进口压力、进口温度为变量时,气膜温度、密封环端面温度随转速、进口温度的增大而增大,随进口压力的增大而减小;开启力随转速、进口压力、进口温度的增大而增大;泄漏率随转速、进口温度的增大而减小,随进口压力的增大而增大。As the most effective strategy to reduce CO_(2)emission, carbon capture, utilization and storage(CCUS) technology has become the focus of global attention under the background of “carbon emission peak, carbon neutrality”. For the centrifugal compressor dry gas seal applied in CCUS technology, the spiral groove dry gas seal was taken as the object, and CO_(2)with impurities was used as the lubricating medium. Based on the equation of state for combustion gases and combustion gas–like mixtures(EOS–CG), the density, enthalpy, sound speed and Joule–Thomson coefficient of CO_(2)mixture were studied. With the consideration of the real gas effect, viscosity–temperature–pressure effect, choked flow effect,centrifugal inertia effect and convective heat transfer between lubricating gas and sealing face, based on the solution of the Reynolds equation, energy equation and heat conduction equation of sealing rings by the finite difference method, the pressure field, temperature field, opening force and leakage rate of the CO_(2)with impurities dry gas seal was analyzed. The results showed that the density of CO_(2)with impurities increases with the increase of the pressure, and the enthalpy, Joule–Thomson coefficient increases with the decrease of the pressure when temperature is constant. The density decreases with the increase of the temperature when pressure keeps constant while an opposite trend is obtained for enthalpy.The sound speed increases as temperature increases while Joule–Thomson coefficient reduces under the same pressure within a lower pressure condition. In addition, when entrance pressure is 12 MPa, inlet temperature is 380 K, rotating speed is 15 000 r/min, outlet pressure is 1.9 MPa, the temperature difference between the inlet and outlet of gas film is about 23 K, and it is about 10 K for sealing ring end face. When the rotating speed, inlet pressure and inlet temperature are regarded as variables, the temperature of gas film and sealing rings increases with the increase of the rotating

关 键 词：CO_(2)捕集利用与封存 含杂质CO_(2) 物性参数 干气密封 温度场 

分 类 号：TH117.2[机械工程—机械设计及理论] TB42[一般工业技术]