Harmonic Resonance and High Cycle Fatigue of a Radial Turbine in Pressure Fluctuation

The pressure fluctuation on blade surface, harmonic vibration and high-cycle fatigue of a radial turbine with variable guide vane were studied. The results show that high-cycle fatigue occurs at the leading edge of blade, which is consistent with the actual damage. The pressure fluctuations are mainly induced by the strong shock in vane suction side and clearance leakage flow in vane tip. The maximum locates at the leading edge of blade. In the pressure fluctuation, the blade resonance is induced, accompanying with different response characteristics and high stress for each blade, which causes blade high cycle fatigue. In this process, the maximum stress locates at the root of the leading edge.