气流激励下某向心涡轮的谐振响应和高周疲劳研究

研究某可调向心涡轮转子叶片表面压力波动特性,以及由此产生的叶片谐振和高周疲劳. 结果表明:涡轮叶片前缘发生高周疲劳破坏,与实际破坏的位置相吻合. 导流叶片尾缘吸力面的强激波和导流叶片叶尖间隙泄漏流是产生压力波动的主要原因,最大压力波动值出现在叶片前缘. 气流压力波动诱发叶片谐振进而产生高周疲劳,振动过程中涡轮各叶片表现出不同的响应特性,同时产生较大动应力,最大应力位于叶片前缘根部. 

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.