减涡器破裂转速预测方法及试验验证

采用数值分析同试验相结合的方法研究了减涡器破裂转速问题。根据减涡器支撑环孔边的应力状态，设计了支撑环结构的模拟试验件，开展了单调拉伸载荷下的破坏试验，得到了体现结构应力特征的破坏参数。进而基于有限元方法，将模拟试验件的破坏参数引入减涡器支撑环破裂转速预测中，并对比了不同破裂准则对破裂转速预测结果的影响。分析表明:所设计的模拟试验件与减涡器支撑环的应力梯度吻合较好，可准确描述结构应力特征；局部塑性法和基于材料强度的方法预测破裂转速时结果更为保守，分别比平均应力法的预测值低15%和23%，对此类结构的破裂分析具有工程参考价值。 

Prediction method and experimental verification of the burst speed of the vortex reducer

The problem of the burst speed of vortex reducer was studied by numerical analysis combined with experiment.According to the stress state of vortex reducer，the simulative specimen was designed，and the failure experiments under the monotonic tensile load were carried out.The failure parameters reflecting the structural stress characteristics were obtained.Furthermore，based on the finite element method，the failure parameters of the simulative specimen were introduced into burst speed prediction of vortex reducer and the influences of different failure criterion on the burst speed prediction were compared.The analysis showed that the stress gradient of simulative specimen was in good agreement with structure，which can accurately describe the structural stress characteristics.Burst speeds calculated by the methods of local plasticity and based on tensile strength of materials were more conservative，which were 15% and 23% lower than those predicted by average stress method，respectively.The method developed has engineering reference value for the failure analysis of structures.