汽轮发电机转子副槽通风冷却系统流动特性研究

在转子副槽通风冷却系统中，副槽结构、径向风道分布、槽楔出风口直径等参数，直接影响转子风道冷却介质流动特性。为减少副槽通风系统转子轴向温差及热应力，必须使转子沿轴向各径向风道内冷却介质流量分配尽可能均匀。针对转子副槽通风系统的结构特点，建立转子绕组通风离散计算模型。并应用该模型对125 MW空冷汽轮发电机转子副槽通风系统进行计算。研究副槽结构、转子槽楔出风口直径、转子径向风道布置等对转子径向风道流量分配的影响。研究结果表明，在相同入口流量下，副槽截面积越大，径向风道流量偏差越小；转子槽楔直径越小，径向风道流量偏差越小；采用变径向风道间距，可使径向风道流量偏差减小。该文的研究结果对汽轮发电机转子副槽通风冷却系统的设计具有指导意义。

Study on the Flow Characteristics of Rotor Sub-slot Ventilation in Turbo-generator

In the rotor winding ventilation system with sub-slot, the configuration parameters of sub slot, the distribution of winding’s cooling ducts, and the diameter of slot wedge directly affect the flow characteristics of coolant in cooling ducts. To reduce temperature difference and thermal stress along axis direction of large turbo generator rotor, the coolant mass flow rate distribution in radius ducts along axis direction of rotor must be uniform. Based on the characteristics of ventilation system with sub-slot, a discrete calculation model of the rotor winding ventilation was built. The computation results of rotor winding ventilation of a 125 MW air-cooled turbine generator with sub-slot had been provided. The effect of the configuration parameters of sub slot, the distribution of winding’s cooling ducts, and the diameter of slot wedge on mass flow rate distribution in radius ducts was presented. The results show that the deviation of the air mass flow in radius ducts along the rotor axis reduces with area of sub-slot increases and diameter of rotor wedge decreases, and change the distant of cooling ducts can reduce the deviation of the air mass flow in radius ducts along the rotor axis, at the same inlet mass flow. The results are helpful for design of the rotor winding ventilation system with sub-slot.