【作者】 陈向阳；

【导师】 袁丹青；

【作者基本信息】 江苏大学 ， 流体机械及工程， 2009， 硕士

【摘要】 反应堆冷却剂泵(以下简称主泵)被喻为反应堆的心脏,属于核Ⅰ级安全泵,它直接关系着整个反应堆的运行状况和安全性能。在进行主泵的设计时,必须全面考虑各种工况,并选择适当的模型进行水力、振动及多相流特性分析,保证其具有很高的安全性和较好的经济性。因此,利用先进的研究手段对主泵内部流场和结构应力场进行分析,对准确揭示其相关规律、保障其安全运行都具有重要的意义。本文从第三代反应堆主要堆型——压水堆的发展现状和特点出发,针对主泵的安全性和经济性问题,运用计算流体力学技术,并结合流固耦合技术对其振动和多相流特性展开了较为广泛的研究。本文的主要工作及研究成果包括:1.总结了主泵的发展过程和研究现状,并进行简要分析,确定了基本研究路线。阐述了轴流式主泵的基本设计理论,分别应用升力法和流线法设计了主泵的叶轮和导叶;2.分别应用Pro/E和ANASYS Workbench软件,对主泵实体和流道进行了三维实体建模及网格划分,并对流场、结构应力场耦合(流固耦合)计算的控制方程、离散求解方法、多相流模拟理论和网格划分技术等进行了简要阐述;3.从主泵的安全和经济性能出发,利用Navier-Stokes方程和标准κ-ε湍流模型对其内部流场进行了数值模拟,根据模拟结果对整体效率和压力脉动进行了深入分析,并通过对比分析提出了优化设计方案,保证了水力部件对整个泵段压力脉动的影响较弱,对主泵机组振动的贡献较小,且具有较好的经济性;4.对高温高压工作环境下的主泵叶片所承受的各种应力进行了理论分析,并利用流固耦合技术,通过求解耦合方程,对稳定工况下的叶片应力进行计算和分析。强度校核结果表明:本文主泵满足美国机械工程师协会的强度要求。为改进叶片翼型设计、保障主泵水力性能和强度要求提供了有效依据;5.根据流场压力脉动特性,对叶片的振动问题进行了深入的理论分析,通过反复利用流固耦合技术,仿真了主泵的模态特性,得到其自振频率和振型,用以保证主泵避免共振;6.针对反应堆冷却剂泄露事故,利用Navier-Stokes方程、两相κ-ε湍流模型和欧拉-欧拉非均相流模型,对主泵内部流场气液两相流流动进行了数值模拟,详细分析了两相流工况下扬程与空泡平均直径、进口处的空泡体积分数和冷却剂温度之间的内在联系,并对主泵的瞬态性能进行了有效预测,其结果可为电机、惰转飞轮等部件的安全设计提供理论依据。更多还原

【Abstract】 Reactor coolant pump (hereinafter referred to as the main pump) that is specified Class I pump is compared to the heart of the reactor, and it has a direct influence on the operation situation and safety performance of reactor. In order to ensure a very high safety and a good economy performance, a variety of working conditions must be taken into account and a proper model has to be chosen for analysis of the hydraulic performance, vibration and multiphase flow characteristics. Therefore, it has important significance to make use of advanced research tools which are used to analyse the internal flow and structure stress field of main pump for revealling its relevant laws and ensuring its safe operation.The current situation and characteristics of the Pressurized Water Reactor (PWR) which is the main type of generation III reactor were reviewed. Aiming the safety and economy performance, this paper deeply discussed the vibration and multiphase flow problem of main pump that the CFD and fluid-solid coupling technology were utilized. The main work and research results of the paper as follows:1. The development and research situation of main pump were introduced briefly, and the specific research program was identified by analysis. Fundamental theory of hydraulic design of axial-flow main pump was elaborated and was applied to design the impeller and guide vane.2. Solid models of body and fluid channel of main pump were generated and meshed by using Pro/E and ANASYS Workbench software. And the control equations of fluid and structure coupling fields, discrete solving methods, simulation theory of multiphase flow and mesh technology were discussed.3. From the safety and economy performance of main pump, the numerical investigation of internal flow that was based on calculation Navier-Stokes equation and standard k-εturbulence model was carried out. The whole efficiency and pressure fluctuation were deeply analyzed based on the simulation results and the optimum design method was advanced. The comprehensive analysis shows that the hydraulic parts could reduce the effects of pressure fluctuation and increase only a few vibrations to whole unit and these are in favor of improving economy performance.4. Theoretical analysis of various stresses of main pump blades that are exposed to working environment of high temperature and high pressure was conducted. And in order to compute and analyze the blade stress, the fluid-solid coupling technique was adopted to solve the coupling equation. The intensity examination proved the intensity of the reactor coolant pump meet the requirement of ASME. This could be used for improving aerofoil design and ensuring performance and intensity.5. According to the pressure fluctuation characteristics, theoretical analysis of blade vibration was proceded deeply. The modal attributions were simulated and the natural frequency and mode shapes were obtained by using fluid-solid coupling technology repeatedly.6. From the leakage condition of reactor coolant pump, numerical simulation of two-phase liquid-gas flow were conducted by calculation Eulerian-Eulerian inhomogeneous model and Navier-Stokes equation with standard k-εturbulence model. The relationships between the head and average diameter of bubble, gas volume fraction and temperature of inlet were opened out respectively. Then the unsteady performance was well predicted and this could provide a theoretical basis for the safety design of flywheel and electromotor.更多还原