Abstract:With the turbo generator’s capacity increasing, the size of rotor coil is lengthened. The ventilation system becomes complicated, and the rotor ventilation system belongs to the multi-path cooling system. In order to reduce axial temperature difference due to the non-uniform ventilation, a physical model of multi-path ventilation structure is presented, combined with a given example of half rotor in the large turbo generator with air cooling; the multi-path ventilation consists of the radial sub slot ventilation, the axial ventilation and the rotor end ventilation. Based on computational fluid dynamics(CFD) principle, the three dimensional turbulent flow field is simulated by finite volume method, and the air mass flow rate of entering rotor end segment, axial ducts and sub slot is obtained. The effect of some structures on the air flow rate distribution of various ventilation segments mentioned above is analyzed. In view of the rotor body, the air flow rate per unit axial length of windings is presented to evaluate the uniformity of ventilation cooling. The method and the conclusion will provide theoretical guidance to the optimization design of the length of the axial and sub slot ventilation of the large generator rotor.
路义萍, 阴文豪, 李俊亭, 韩家德, 曹文. 汽轮发电机转子端部及槽内供风量分布特性[J]. 电工技术学报, 2010, 25(4): 38-43.
Lu Yiping, Yin Wenhao, Li Junting, Han Jiade, Cao Wen. Distribution Characteristic of Air Flow Rate in Rotor End and Inner Slot of Turbo Generator. Transactions of China Electrotechnical Society, 2010, 25(4): 38-43.
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