Study On Flow Field Of Bearing Cooling System Of Hydroelectric Generating Unit

With the development of modern hydropower technology,the application of large and super large turbine generator units is increasing,which has an increasing impact on stability,security and reliability of power network operation,so the operational stability of the unit must be ensured.The bearing system of the hydroelectric generating unit is an important part to ensure the safe and stable operation of the unit,In the actual production process,Because the unit eccentric,bearing cooling system oil circuit is unreasonable,lubricating oil quality deterioration and other factors,bearing system cooling performance is not good and bearing tile temperature is too high or even burning phenomenon occurs,which not only affects the service life of bearing,but also bring a serious threat to the safety of power production.This paper is based on a large number of technical literature and hydropower station site investigation,according to the actual engineering needs,use Fluent software to study the internal flow field of the inner circulating cooling system of the thrust bearing of the hydro-generator unit.By analyzing the distribution rules of velocity,pressure and temperature,the technical assistance for the optimization design and safe operation of the bearing oil circulation cooling system of unit is provided.The main work is as follows:1.This paper establishes the mathematical model of lubricating oil in the bearing oil circulation cooling system,then the basic methods of numerical simulation and the software used in the research process are introduced,and the process of computational fluid dynamics is described.2.According to the actual geometrical dimensions of the oil circulating cooling system of the hydrogenerator thrust bearing,a three-dimensional geometric model is established by using modeling software SolidWorks,then the ICEM software is used to mesh the computational domain and then the corresponding boundary conditions are set.3.According to conditions identified by the temperature of thrust bearing,oil and water,using the fluent software to calculate the speed,pressure and temperature distribution of the oil within the bearing oil tank.4.The calculation results of different working conditions are compared and analyzed to find out the rules and provide reference for structure optimization of thrust bearing oil circulation cooling System,the safe and stable operation of the unit and installation and maintenance of other similar power stations in the country.