• CN:11-2187/TH
  • ISSN:0577-6686

›› 2014, Vol. 50 ›› Issue (18): 162-166.

• 论文 • 上一篇    下一篇

弯曲残余应力对转子蠕变性能的影响研究

孙燕平;庞春凤   

  1. 华北电力科学研究院有限责任公司
  • 发布日期:2014-09-20

Research on Structural Strength for Hot Water Circulation Pump Based on Thermal-structural Coupling

KONG Fanyu;XIA Bin;ZHANG Hui;HE Yuyang   

  1. Research Center of Fluid Engineering and Technology, Jiangsu University
  • Published:2014-09-20

摘要: 针对某600 MW火力发电机组高中压合缸汽轮机转子的中部弯曲进行分析,认为高温蠕变和残余应力的耦合作用是导致转子发生塑性永久变形的主要原因。首先按照转子结构图利用有限元软件ANSYS建立精细化的三维实体模型,并进行温度场和应力场的有限元分析。在此基础上对高中压转子进行热-固耦合分析,通过对转子材料蠕变试验数据进行处理,得到Norton蠕变模型参数,并在ANSYS中对转子的高温蠕变和残余应力进行有限元仿真。研究表明,单纯的高温蠕变不足以引起转子在启动过程中发生弯曲,耦合残余应力的作用后该高中压转子会在很短时间内发生弯曲值超标,选取Norton三参数模型和残余应力生成方法比较有效。该研究对高中压合缸转子中部弯曲原因分析具有借鉴和指导作用。

关键词: 转子弯曲;高温蠕变;残余应力;ANSYS

Abstract: Hot water circulation pump is widely used to various pressurization equipments. The structural safety and reliability closely relates to the normal operation of whole unit. A thermal-structural coupling method is applied to verify the structural reliability of hot water circulation pump. Based on the pump performance test, temperature, the equivalent stress and total deformation of the structure, under different medium temperature conditions, are calculated respectively. The temperature and absolute pressure of the fluid domain are also calculated when the medium temperature changes. Then, the effect of different medium temperature on each quantity is analysed. Based on the fourth strength theory, the strength check analysis in the pump casing structure is implemented. The results show that the values of equivalent stress and deformation, caused by temperature load, are greater than ones, caused by pressure load. The effect of temperature on structural strength can not be ignored especially for the medium temperature higher than the room conditions. With medium temperature rising, the structural temperature of pump increases. The temperature in pump body is higher than the one in pump bracket. But the gradient of temperature is smaller. The position of stress concentration is located at the tongue. Therefore, confirming the shape and location of the tongue is particularly important in the process of designing. The strength check result shows that the pump casing structure can meet the strength requirement when the medium temperature equals to 25 ℃and 40 ℃ respectively.

Key words: thermal-structural coupling;thermal stress;fluid solid coupling;hot water circulation pump;structural strength

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