The analysis of flow field in the generator ventilation channel

Air cooling is the most commonly used cooling method for hydraulic generators. Heat is exchanged and transmitted from heating structure to the radiator by the cooling air. The quality of ventilation structure design determines the heat dissipation of the generators. The CFD numerical simulation was performed on stator and rotor flow field, and flow conditions were calculated and analyzed. The model researched in the paper was an air cooling system used in a generator of 1000MW water turbines. Compounded faces and periodic model were used to simplify the structure of the whole cooling system. The standard κ-ε turbulence model was used to simulate the influence of turbulence in the ventilation channels. Drag coefficients of rotor ventilation channels, rotor cores and stator ventilation channels were calculated respectively using the calculation results. Through the research, how the flow field was influenced by the structure of ventilation channel was obtained.