机匣安装边螺栓连接结构抗冲击性能评价指标

Impact Resistance Evaluation Index of Aeroengine Casing with Bolted Flanges

针对航空发动机机匣安装边螺栓连接结构的抗冲击问题,对现有研究中适用于机匣包容性的评价指标进行了总结与比较,提出了螺栓能量密度的评价指标。分别以螺栓内能占比和螺栓能量密度2种评价指标进行了机匣安装边螺栓连接结构几何参数对其抗冲击性能的影响研究,通过数据对比验证了以螺栓能量密度作为评价指标的可行性与合理性。结果表明:随着安装边高度、螺栓直径、螺栓数的增加,螺栓内能占比逐渐降低;随着机匣壁厚的增加,螺栓内能占比呈现与实际不符的先降低后提高的趋势。安装边高度、螺栓直径、螺栓数和机匣壁厚与螺栓能量密度皆呈负相关;在数值仿真中以螺栓能量密度作为评价指标可以更好地反映螺栓连接结构抗冲击能力的同时具有更高的效率。

Aiming at the impact resistance of aeroengine casing with bolted flanges,the evaluation indexes applicable to casing containment in existing studies were summarized and compared.The evaluation index of bolt energy density was proposed.The effect of the geometric parameters of the bolt connection structure on its impact resistance was studied considering two evaluation indexes,namely the bolt internal energy ratio and the bolt energy density.The feasibility and rationality of using bolt energy density as the evaluation index were verified through data comparison.The results show that with the increase of the flange height,the bolt diameter,and the number of bolts,the bolt internal energy ratio decreases gradually.With the increase of the casing thickness,the bolt internal energy ratio shows a trend of first decreasing and then increasing,which is inconsistent with the actual situation.The flange height,the bolt diameter,the number of bolts,and the casing thickness are negatively correlated with the bolt energy density.Taking bolt energy density as the evalua⁃tion index in the numerical simulation can better reflect the impact resistance of bolted structures and have higher efficiency.