Numerical Analysis Of Fluid Field&Thermal Field In Side Wind—Generator

In recent years, the development of wind power industry in China is booming in a burst due to the policy lunched by the state government with the purpose to foster the industry with increasing efforts, as well as the sense of energy crisis spreading around the world. However, we need a rapid and healthy development of wind power business whether based on the consideration of cultivating new economic growth points and improving China’s industrial competitive force or with the intention to reduce environment pollution caused by energy generation and to face the challenge of global warming. All in all, at present, the existing technology problems, such as excessive motor temperature rise and excessive noise, seriously restrain the further development of wind power business in our company.In this thesis, it despribes how to use ANSYS FLUENT simulation software to perform the fluid dynamics and temperature field simulation analysis for3MW and5MW wind power generators, how to adjust the technical parameters of the generator to improve the cooling effect of the generator to meet the system requirements based on the simulation analysis results so as to greatly reduce development cycle and development costs. This paper introduces the background of the subject and explains the strategic significance of the project for our company, and interprets the analysis process of fluid dynamics and temperature field simulation of3MW and5MW generators in details, carefully investigates the analysis results of fluid field and temperature field, offers practicable improvement measures, and varifies the results with test data, and finally achieves a satisfied end.Heat transfer and operating performance of generator are closely related to the ventilation structure and fluid flow behaviour. Taken a5MW large doubly-fed wind generator and a3MW permant magnent wind generator as examples, present basic hypothesis and boundary condition, physical model of three dimensional fluid and temperature coupled field was established according to hydromechanics and heat transfer theory. On the base of the correctness of researching method and computing result proved by the temperature rise distribution of the whole generator, the space distribution characters of different cooling medium inner generator, such as flow velocity, path line, temperature rise and heat transfer coefficient, were analysed numerically using finite volume method. Rheological properties of cooling medium inner generator was obtained, by which a theory gist for design of ventilation structure for the same type generator and accurate calculation of fluid fields for the larger capacity wind generator is provided.