考虑螺栓力学特性的两级机匣连接结构有限元建模及振动分析  

Finite element modeling and vibration analysis of two-stage casing connection structure considering mechanical properties of bolts

作　　者：李浩 孙伟[1,2] 徐昆鹏 刘宏浩 LI Hao;SUN Wei;XU Kunpeng;LIU Honghao(School of Mechanical Engineering&Automation,Northeastern University,Shenyang 110819,China;Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China,Northeastern University,Shenyang 110819,China)

机构地区：[1]东北大学机械工程与自动化学院,辽宁沈阳110819 [2]东北大学航空动力装备振动及控制教育部重点实验室,辽宁沈阳110819

出　　处：《中南大学学报(自然科学版)》2025年第2期501-513,共13页Journal of Central South University:Science and Technology

基　　金：国家科技重大专项(J2022-Ⅳ-0005-0022)

摘　　要：航空发动机的各级机匣通过螺栓法兰连在一起形成完整的机匣连接结构,法兰边上的螺栓结合部力学参数对机匣结构的动力学特性产生明显的影响,只有对机匣连接结构进行动力学建模并进行合理的设计才能保证其具有优越的动力学性能。以两级机匣连接结构模拟件为对象,在考虑螺栓力学特性的基础上,提出采用ANSYS软件对其进行有限元建模的方法。两级机匣连接结构有限元建模主要包括机匣内、外壳的模拟、静子叶片的模拟以及法兰边上螺栓结合部的模拟。分别采用实体单元、刚性耦合的梁单元、弹簧单元、虚拟材料4种方式模拟机匣法兰边上螺栓结合部并给出其引入机匣连接结构的方式。采用实例研究验证模型的合理性。首先,用机匣1有限元模型求解固有频率及模态振型,并结合试验采用反推辨识法获得模拟边界条件的弹簧单元参数;其次,用包含不同螺栓结合部模型的两级机匣连接结构有限元模型求解固有频率及模态振型,并用试验验证其合理性。从计算精度、耗时、建模复杂程度三方面对比两级机匣连接处4种螺栓结合部模拟方法的优缺点。研究结果表明:采用刚性耦合的梁单元模拟螺栓结合部的计算精度与实体单元的计算精度最相近,计算时间减少了44.5%,可在实际机匣连接结构有限元建模时优先选用。All stages of aero-engine casings are connected together by bolted flanges to form a complete casing connection structure.The mechanical parameters of the bolted joints on the flange edge will have a significant impact on the dynamic characteristics of the casing structure.Only by modeling and designing the casing connection structure reasonably can its superior dynamic performance be ensured.Based on the mechanical characteristics of bolts,the finite element modeling method of the two-stage casing connection structure simulator using the ANSYS software was proposed.The finite element modeling of the two-stage casing connection structure include the simulation of casing inner and outer shells,the simulation of the stator blade,and the simulation of the bolted joint on the flange side.In particular,the bolted joints on the casing flange are simulated by means of solid element,rigid coupling beam element,spring element and virtual material respectively,and the way of introducing the bolted joints into the casing connection structure was also given.A case study was carried out to verify the rationality of the model.Firstly,the natural frequency and mode shapes were solved by the finite element model of casing 1,and the spring element parameters of the simulated boundary conditions were obtained by using the inverse identification method in combination with the experiments;secondly,the natural frequencies and modal shapes of two-stage casing were calculated by the finite element model with different modelling method of bolt joints,and the rationality of the above model was proved by experiments.Furthermore,the advantages and disadvantages of four simulation methods for bolted joints at the location of casing connection were compared from three aspects:calculation accuracy,time-consuming,and modeling complexity.The results show that the use of rigidly coupled beam element to simulate the bolted joints has the closest accuracy to that of the solid element,and the time decreasing rate is 44.5%,which can be preferred in

关 键 词：两级机匣 连接结构 螺栓结合部 有限元建模 振动分析 

分 类 号：TB123[理学—工程力学] V236[理学—力学]