针对航空发动机涡轮导叶开裂故障，通过对故障叶片冲击冷却后腔与主流流动的耦合分析，得出了故障的主要原因：故障部位内腔冲击冷却的冷气流速较低、冷气流量分配不均导致冷却不足，长时间高温工作后，内外壁压差使得叶背区域发生蠕变变形，最终形成鼓包并开裂。通过调整冲击孔径、孔数和孔排布，使得冲击冷气的流量分配更均匀，冲击流速更高，更有效地冷却叶片壁面，减小叶片后腔内外壁压差。初步计算验证表明，该改进措施有效。%Through the flow coupling analysis of the aft-cavity and the main flow passage for the crack sta⁃tor, the main reasons for the crack were that the un-even mass flow distribution of impingement and the low velocity of the impingement caused the shortage of cooling, after long duration of working under the high temperature and the high pressure difference in and out of the blade wall, a bulging of the wall formed and then cracked. And the improvement design by the adjustment of the radius, number and arrangement of the impingement holes was used to make the mass flow distribution of impingement more even, improve the im⁃pingement velocity for a more effective coolant for the stator. Another effect of the improvement was the re⁃duction of the pressure difference outside and inside the stator. The improvement design was proved to be valid by calculation.
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