吸入式空冷汽轮发电机气体运动流场分析及应用

为了提高空冷汽轮发电机的冷却效果,改变原压入式空冷汽轮发电机通风方式,空气由定子风道和转子风道进口进入,由吸入式风扇排出,消除了原压入式汽轮发电机由于风扇进风而带来的风道进口温度升高以及转子风道的热风进入定子风道造成定子风道进风口温度增加,改善了冷却效果。采用模型试验和数值模拟方法对吸入式空冷汽轮发电机风道气体运动流场进行了分析,结果表明：吸入式空冷汽轮发电机转子风道进口风速一般为10.0~90.0m/s,和压入式空冷汽轮发电机转子风道进口风速基本相同;距汽端近1.0m范围内,定子风道风速一般为8.0~18.0m/s,距汽端1.5~3.0m范围内,定子风道中风速仅为3.0~5.0m/s,为了使定子得到均匀冷却,将前15个风道间距增加至80.0mm,后25个风道间距减小至45.0mm,可在总风道数目基本不变的情况下改善冷却效果。

Analysis and application of the flow field in ventilation ducts of intake air turb-type generator

In order to improve the cooling effect of air turb-type generator,the ventilation construction of air turb-type generator was modified such that the indraft air moved into stator and rotator ducts and exhausted through fan.The advantage of the modification was that the temperature rise at the entrances of stator and rotator ducts was eliminated and the cooling effect of air turb-type generator was improved.Based on ventilation construction of a exhaust air turb-type generator,the flow field was analyzed by model test and numerical simulation.It was found that the air velocity in rotator ducts was about 10.0~90.0m/s and air velocity in stator ducts was about 8.0~18.0m/s around the front parts and about 3.0~5.0m/s around the rear parts.In order to improve the uniformity of the stator cooling effects,the ventilation construction of stator should be adjusted in such a way that the distance of the adjacent ducts to be increased to about 80.0mm at front parts and reduced to about 45.0mm at rear parts.