【作者】 胡玄；

【导师】 王凤岐；

【作者基本信息】 天津大学 ， 机械制造及其自动化， 2007， 硕士

【摘要】 水轮发电机通风散热的计算是发电机设计中的主要内容之一,它直接关系到电机的寿命和运行的可靠性。准确的通风散热计算对电机的设计和运行具有重要意义。以往在进行水轮发电机发热分析时,都是孤立地求解温度场,而很少考虑热源及通风结构与温度及其分布之间的相互影响。本文采用一种综合算法,将水轮发电机的通风和散热联系起来,从而构成通风散热的综合计算方法。本文的研究工作对于提高电机设计制造中材料利用率以及电机运行中的可靠性,具有重要意义。论文主要进行了以下方面的工作。1.将水轮发电机通风和散热联系起来进行综合计算研究。分别在所考虑的区域上建立起通风系统的三维流场模型和定子三维温度场模型,并以温度场边界表面散热系数的计算作为这两个模型计算的媒介,从而构成通风发热的综合计算方法。2.以计算流体力学(CFD)软件FLUENT为工具,对灯泡贯流式水轮发电机通风系统的流场进行了数值模拟。该方法建立了灯泡贯流式水轮发电机通风系统的三维几何通风模型,用标准κ-ε湍流模型作为气流的物理模型,并对计算出的电机空气风量分配情况与实测数据和传统计算结果进行比较,验证了数值模拟的可靠性。研究表明在合理的简化条件下,采用CFD能准确的模拟灯泡贯流式水轮发电机的通风系统流场,为进行灯泡贯流式水轮发电机通风系统设计和优化提供有效的依据。计算得出的电机各部分空气风速将会作为定子温度场计算的初始条件。3.以有限元软件ANSYS为工具,对灯泡贯流式水轮发电机的定子温度场进行数值模拟。根据通风系统的特点,做相应的假设,得出计算定子的温度场的简化模型。根据模型特点,采用Vsweep方式划分网格,由通风系统模拟得出的风速计算出定子表面散热系数。并对模拟出来的定子温升情况与实测数据和传统计算方法的计算结果进行比较,验证了数值模拟的可靠性。更多还原

【Abstract】 The ventilation and heat dispersion’s calculation of the hydrogenerator is one of the most design contents, and they are directly related to the life of generator and the reliability of operation. In the past, when the heating problem of hydrogenerator was concerned, the temperature field was individually solved regardless of the interactions among thermal source, ventilation structure, temperature and its distribution. In this paper, a synthetically algorithm related to the ventilation and heat of an electric machine is adopted. The research in this paper is very important to raise material utilization during the machine design and manufacture and reliability during the operation of the machine.The content of this paper is:1. The research on synthetically algorithm related to the ventilation and heat of an electric machine is developed. The three-dimensional model of the ventilation system and the three-dimensional temperature field model of stator were constructed separately on the considering area, and the surface heat transfer coefficient calculation of the temperature field was taken as a medium to the two models, thereby the synthetically algorithm process of the ventilation and heat dispersion was built.2. The flow field of the ventilation system for the flow-bulb hydrogenerator was simulated by applying the CFD software FLUENT. Using the standardκ-εturbulence model as the physical model, a three-dimensional model for the ventilation system of the flow-bulb hydrogenerator was constructed, and the reliability of numerical simulation was validated by comparing the simulated results of the air distribution with the measured data from the electrical machine. The research indicates that the ventilation system of the flow-bulb hydrogenerator can be accurately simulated by CFD, which provides basis for the design and the optimization of the ventilation system of the flow-bulb hydrogenerator. The velocity of air in the electrical machine will be used as initial condition in the calculation of the three-dimensional temperature field of stator.3. The three-dimensional temperature field of stator for Flow-bulb Hydrogenerator was simulated by applying the FEA software ANSYS. According to the characteristics of the ventilation structure, the finite-element model of the temperature field calculation was constructed. The model was transformed to the finite element model by the Vsweep way. The surface heat transfer coefficient can be calculated by using the velocity of air in the electrical machine which was known in numerical simulation of the ventilation system. The reliability of numerical simulation was validated by comparing the simulated results of the temperature field with the measured data from the electrical machine.更多还原