水轮机过机流量测量分析

Analysis on measurement of flow passing through hydraulic turbine

利用差压变送器测量流量在水电站中非常普遍,该测量方式运用了水流在蜗壳中流动时遵循等速度矩规律,结合伯努利方程及水流相似定律求得流量与压力差间的关系,再经处理计算出流量。很多水电站使用差压变送器时效果并不理想,从经验安装和数据处理的角度出发,对测量值偏差的原因进行了分析,给出了相应的应对方法。

The flow measurement method by using differential pressure transmitter is used in hydropower stations currently.In this method,according to that the water flow in the volute casing abides by the law of constant velocity torque,combining with the Bernoulli equation and the water flow similarity law,the relation between the flow and the pressure difference can be obtained;and by processing,the flow can be calculated.The effects of differential pressure transmitter use are not ideal in many hydropower stations.Starting from the angles of experience,installation and data processing,the reasons of deviation of measured value were analyzed;and relevant solutions were given.