Analysis Of Thermal And Flow Field Of 135MW Air-cooling Turbo-generator

With the rapid development of economic, the demand for energy and resources is more and more, especially the growing demand for electricity. Currently, the electricity turbo-generator produced whose single capacity is growing. Heat dissipation effect directly affect the safe operation of the turbogenerator. There are several ventilation cooling methods for large turbo-generator. Due to restrictions of the computer before, numerical simulation has not received enough attention. Now the computer technology is developed rapidly, which provides guarantee for numerical simulation of the ventilation cooling structure in turbo-generator.The 135 MW turbo-generator which is developed by the factory is as research object. According to the size provided by the factory, integration three dimensional physical model that contained stator, stator end, rotor, rotor end and air gap was established. The air volume entering into the rotor, air gap and stator was automatic distribution and more close to reality, which had actual meaning for numerical simulation and analysis of flow and temperature fields of the generator.Firstly, the eighth slot and its corresponding stator slot that had longest wind path were regarded as the research object. Because of the structure of two-way ventilation, the structure was symmetrical. So, the semi axis of eighth slot and its corresponding rotor slot was considered as three-dimensional physical model. Under the speed velocity of 3000 r/min, the distribution of static pressure, relative speed and air volume was given through number simulation, comparing with the air volume providing by factory. The results were within the acceptable range of error and causes of result error were analyzed.Secondly, three-dimensional flow field and temperature field of coupled solution model were established. The temperature distribution of the cooling air, the temperature rise of stator and rotor was analyzed and analyzed the rise of temperature of the stator and rotor main components. Certainly, the highest temperature rise area of the different structure was found and the causes of formation of high temperature were analyzed, and then, the unreasonable areas of ventilation structure were optimized. In this paper, research methods and conclusions can provide theoretical basis for the design and optimization transformation of the turbo-generator.