汽轮发电机带有交替径向风道的转子流体与传热耦合分析

Regarding the issue of rotor heating and cooling in a turbogenerator rotor with alternate radial ventilation ducts, a 350 MW water-hydrogen-hydrogen-cooled turbogenerator was selected as the research object. Based on the basic theories of fluid mechanics and heat transfer, a global ventilation fluid network model was firstly established, taking into account the rotation. The branch flow and node pressure were calculated using a successive iteration method. Then, a three-dimensional physical and mathematical model of fluid-heat transfer in a generator rotor with alternate radial ducts was established, and the basic assumptions and corresponding boundary conditions were given. At the same time, the results from the ventilation network were used as the coupling boundary of the rotor solution domain, and the finite volume method was used for coupling calculation. The calculated results match well with the measured values. Then, the flow distribution and hydrogen flow in the alternate radial ducts were analyzed, and the hydrogen temperature distribution inside the rotor and the temperature variation at the slot wedge outlet were studied. The axial temperature distribution characteristics of the rotor winding and iron core were explored. Furthermore, the effects of the inlet flow rate of the sub-slot and the outlet diameter on the rotor fluid and temperature were discussed. The inlet flow rate of the sub-slot should be controlled within the range of 0. 1 m³ / s - 0. 16 m³ / s, and a smaller slot wedge outlet diameter should be selected to improve the efficiency of the ventilation system and the uniformity of air volume distribution, and reduce the axial thermal imbalance.