瑞丽江一级水电站2号水轮机自然补气系统的改进

The Improvement for the Air Admission System of No.2 Turbine in Ruilijiang HydroPower Station

针对瑞丽江一级水电站出现的当机组出力接近额定出力时水轮机尾水管进人门处会发出较强烈的水流撞击尾水锥管壁的声音且尾水平台处有明显振感现象,经现场试验及实地勘察,初步断定上述现象是由于自然补气系统不畅、补气量不足、无法消除或减弱涡带现象所致。上述判断被强迫补气试验所证实。瑞丽江一级水电站2号水轮机自然补气系统补气管路通畅后,进人门处噪声及尾水平台处振感均未再发生。一年多的运行实践证明,对瑞丽江一级水电站2号水轮机自然补气系统的改进是成功的,该经验可以在具有类似现象的电站推广应用。

When the operating condition of No.2 turbine in Ruilijiang hydropower station is close to the rated output,a strong noise of impact on the draft tube cone caused by current near the man door appears,and meanwhile a remarkable vibration comes forth at the draft tube platform.According to the on-site investigation,a preliminary conclusion can be drawn that the reason leading to above-mentioned phenomena is block of air admission system and lack of air so that vortex can＇t be eliminated or even alleviated.The conclusion mentioned above is testified by on-site forced air admission test.After the pipes of air admission system unobstructed,those phenomena never happened again.The improvement of air admission system of Ruilijiang hydropower station No.2 turbine is proved to be successful,and the experience should be applied as a solution to the similar phenomena of other units.