水轮机流量效率测量方式的确定

介绍国内外大型水力机组水力性能现场流量效率试验现状.分析原型与模型试验间的差异及对比试验。提出对比试验必须满足1)所选试验电站符合IEC规程;2)各参与方均未作过试验的电站,各单次流量处理模式共同认可;3)同一稳定工况多次测流,采用共定的误差计算方法;4)同时测蜗壳压差,算出流量与此压差方根线性相关系数,才能作出正确的对比衡量。分析测流的压力时间法、流速仪法、超声波法和蜗壳压差法,对比其优缺点,推荐国内大型和巨型水轮机效率验收试验采用新的压力时间法,并建议按必须满足的条件和要求,在同一机组上作几种对比效率试验,以确定国内水轮机测流方式.

Determination on Measuring Way of Water Turbine Flow and Efficiency

The present states of flow and efficiency site test for the performance measurement of large water power set at home and abroad are introduced. The difference between prototype and model and its' contrast test are analyzed,The contrast test must satisfy following advanced, 1 . Selected test water power station accords with IEC regulations; 2 . The power station is not tested by all side of participants,treatment mode of each one flow value is together appsoved; 3. Flow is measured many a time at same steady operating mode, using together decided error caculation methed; 4. At the same, Volute pressure difference is measured, calculating the linear correlative coefficient between flow and square root of the prssure difference. Then a right contrast consideration and judgement can be given. the flow measuring methods of pressure-time, flow velometer, ultrasonic and volute pressure difference are analyzed. Its advantages and shortages are contrasted. New pressure-time methed is recommended used for the efficiency acceptance test of internal large and giant water turbine, and suggesting in accordance with ne-cessorily satisfied conditions and demands, at the same set several contrast efficiency tests are carried out, to determine the ways of flow measuring for internal water turbines.