热流固耦合下不同载荷对光热熔盐泵转子运行稳定性的影响  

Influence of Different Loads on Operational Stability of Photothermal Molten Salt Pump Rotor Under Thermal-fluid-solid Coupling

作　　者：权辉[1,2] 卢胜 杜朝辉 杜媛英[1] 李一飞 钱晨[1,4] QUAN Hui;LU Sheng;DU Zhaohui;DU Yuanying;LI Yifei;QIAN Chen(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050;Key Laboratory of Advanced Pumps Valves and Fluid Control System of the Ministry of Education,Lanzhou University of Technology,Lanzhou,Gansu 730050;Qinghai Minzu University,Xining,Qinghai 810007;Shouhang High-tech Energy Technology Co.,Ltd.,Jiuquan,Gansu 735000)

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050 [2]兰州理工大学特种泵阀及流控系统教育部重点实验室,甘肃兰州730050 [3]青海民族大学,青海西宁810007 [4]首航高科能源技术股份有限公司,甘肃酒泉735000

出　　处：《液压与气动》2024年第9期108-116,共9页Chinese Hydraulics & Pneumatics

基　　金：甘肃省重点研发计划项目(24YFGA0056);甘肃省陇原创新创业人才项目(2022年度人才发展专项)(2022LQGR51);甘肃省教育厅高校科研创新平台重大培育项目(2024CXPT-09)。

摘　　要：光热电站熔盐泵转子系统由于其自身结构及外部载荷激励,在极端运行工况下难以维持运行稳定性。针对该问题建立有限元模型,分析了温度载荷、流场力载荷、离心力载荷等对熔盐泵转子的应力变形规律;设置4种不同轴段长度的转子模型,分析不同转子模态振型、固有频率以及临界转速等动力学特性。研究发现:转子结构中最大等效应力出现在首级叶轮叶片进口与前盖板交界处,最大变形出现在首级叶轮前盖板尾缘处,流场载荷与质量力载荷使应力与变形在叶轮上大致呈现中心对称分布,温度载荷使得叶轮产生较大的形变;对首级叶轮进行强度校核后,所选材料满足结构强度要求。模型转子的固有频率随中间轴段长度的增加而降低,湿态转子模型的固有频率略低于干态固有频率;其他转子的一阶临界转速均小于转子的设计转速,只有A9转子的临界转速满足±10%安全裕度,不易在运行过程中发生共振。研究结果对于该类型泵安全稳定运行以及在能源应用等领域具有重要的指导意义。The rotor system of the molten salt pump in a solar thermal power plant is difficult to maintain operational stability under extreme operating conditions due to its own structure and external load excitation.To address this issue,a finite element model is established to analyze the stress and deformation laws of the rotor of the molten salt pump under temperature load,flow field force load,centrifugal force and other loads.Four rotor models with different axis segment lengths are set up to analyze the dynamic characteristics of different rotor modes,natural frequencies and critical speeds.It is found that the maximum equivalent stress in the rotor structure occurs at the junction of the inlet of the first stage impeller blade and the front cover plate,and the maximum deformation occurs at the tail edge of the front cover plate of the first stage impeller.The flow field load and mass force load make the stress and deformation approximately present a central symmetrical distribution on the impeller,and the temperature load makes the impeller produce large deformation.After checking the strength of the first stage impeller,the selected materials meet the structural strength requirements.The natural frequency of the model rotor decreases with the increase of the intermediate shaft length,and the natural frequency of the wet rotor model is slightly lower than that of the dry rotor model.The first-order critical speed of other rotors is less than the design speed of the rotor,and only the critical speed of A9 rotor meets the safety margin of±10%,which is not easy to resonate during operation.This research has important guiding significance for the safe and stable operation of this type of pump,as well as in the field of energy applications.

关 键 词：光热发电 高温熔盐泵 热流固耦合 应力应变分析 临界转速 

分 类 号：TH137[机械工程—机械制造及自动化] TM615[电气工程—电力系统及自动化]