The Noise Analysis for Draft Tube of Turbine
We take the field test data from the entrance to the draft tube of the turbine of a hydropower station as an example, the signals acquired are depicted in time domain and frequency spectrum, and the relation between the noise and the load is analyzed, then we find out the reasons which cause noise and put forward the measures for noise elimination. After analyzing the noise signals of the draft tube under different loads, the experimental results show that when the unit operates in load 19MW - 80MW and 138MW - 179MW, the noise is much larger than usual, the abnormal noise is mainly caused by the hydraulic pressure fluctuation of draft tube, the best way to eliminate the noise is the reasonable air compensation for the draft tube.