When the modern aircraft flies, the thin-walled structure of the engine will be exposed to an extremely high-temperature environment, leading to the dynamic response of large deflection and fatigue damage. In order to obtain the structural dynamic responses of the structure in the high speed heat flux and the time of fatigue damage, which are generally difficult to measure, this paper adopts the method of coupled FEM/BEM for numerically simulate analysis and thermo-acoustic fatigue test. A numerical simulation model that is exactly of the same size as the test piece is constructed according to the load effect, and the thin wall structure under the thermo-acoustic load is simulated and calculated. The Power Spectral Density (PSD) method is used to analyze the peak frequency response to acoustic load variation, and the improved rain-flow counting method is used to analyze statistically the vibro-acoustic response data. The fatigue life time of the structure is then obtained. A comparison of the simulation results of acoustic response with the experimental results shows that the error is less than 2%, which verifies the reliability of the numerical simulation. A numerical simulation analysis of the thin-walled structure under the impact of high speed heat flux is carried out. The variation rules of stress response and life of the structure with temperature and flow velocity are summarized, and the reasons for the variation are expounded. The work completed in this paper can provide an important basis for response analysis and life prediction of thin-walled structures in high speed heat flux environment.
[1] LEE J. Large-amplitude plate vibration in an elevated thermal environment:WL-TR-92-3049[R].Washington,D.C.:NASA;1992.
[2] LEE J. Displacement and strain statistics of thermally buckled plates[C]//40th Structures, Structural Dynamics, and Materials Conference and Exhibit. Reston, VA:AIAA, 1999.
[3] MEI C, CHEN R R. Finite element nonlinear random response of composite panels of arbitrary shape to acoustic and thermal loads:WL-TR-1997-3085[R]. Washington,D.C.:NASA;1997.
[4] DHAINAUT J M, MEI C, SPOTTSWOOD S M, et al. Sonic fatigue design and nonlinear panel response to flight nonwhite pressure fluctuations:AIAA-2002-1635[R].Reston,VA:AIAA;2002.
[5] DHAINAUT J M, GUO X, MEI C,et al. Nonlinear random response of panels in an elevated thermal-acoustic environment[J]. Journal of Aircraft,2003, 40(4):683-691.
[6] SCHNEIDER C W. Acoustic fatigue of aircraft structures at elevated temperatures[C]//Aeroacoustics Conference, 1973.
[7] MAEKAWA S. On the sonic fatigue life estimation of skin structures at room and elevated temperatures[J]. Journal of Sound and Vibration, 1982, 80(1):41-59.
[8] PRZEKOP A, RIZZE S A, SWEITZER K A. An investigation of high-cycle fatigue models for metallic structures exhibiting snap-through response[J]. International Journal of Fatigue,2008, 30(9):1579-1598.
[9] NG C F,CLEVENSON S A. High-intensity acoustic tests of athermally stressed plate[J]. Journal of Aircraft,1991,28(4):275-281.
[10] JACOBS J H,GRUENSFELDE R C,HEDGECOCK C E. Thermal-acoustic fatigue of ceramic matrix composite materials[C]//AIAA/ASME/ASCE/AHS/ASC 34th Structures, Structural Dynamics, and Materials Conference.Reston,VA:AIAA;1993.
[11] 杨雄伟,李跃明,耿谦. 基于混合FE-SEA法高温环境飞行器宽频声振特性分析[J]. 航空学报,2011,32(11):1851-1859. YANG X W, LI Y M, GENG Q. Broadband vibro-acoustic response of aircraft in high temperature environment based on hybrid FE-SEA[J]. Acta Aeronautica et Astronautica Sinica, 2011, 32(11):1851-1859(in Chinese).
[12] 桂业伟,刘磊,代光月,等. 高超声速飞行器流-热-固耦合研究现状与软件开发[J].航空学报,2017,38(7):020844. GUI Y W, LIU L, DAI G Y, et al. Research status of hypersonic vehicle fluid-thermal-solid coupling and software development[J]. Acta Aeronautica et Astronautica Sinica, 2017,38(7):020844(in Chinese).
[13] 马艳红, 张大义, 洪杰,等. 气流激励下叶片的高周疲劳概率寿命预估[J]. 推进技术, 2009, 30(4):462-467. MA Y H, ZHANG D Y, HONG J, et al. Prediction on high cycle life of blades using probability method.[J].Journal of Propulsion Technology, 2009, 30(4):462-467(in Chinese).
[14] 洪志亮,赵国昌,杨明绥,等.航空发动机压气机内部流体诱发声共振研究进展[J].航空学报,2019,40(11):123139. HONG Z L, ZHAO G C, YANG M S, et al. An overview on flow induced acoustic resonance in aeroengine compressors[J]. Acta Aeronautica et Astronautica Sinica,2019,40(11):123139(in Chinese).
[15] 沙云东, 魏静, 高志军. 热声载荷作用下薄壁结构的非线性响应特性[J]. 航空学报, 2013, 34(6):1336-1346. SHA Y D, WEI J, GAO Z J. Nonlinear characteristics of thin-walled structures under thermo-acoustic loadings[J]. Acta Aeronautica et Astronautica Sinica, 2013, 34(6):1336-1346(in Chinese).
[16] 沙云东, 胡翼飞, 胡增辉. 薄壁结构高温随机振动疲劳分析方法有效性验证[J]. 推进技术, 2018,39(6):1386-1395. SHA Y D, HU Y F, HU Z H. Random vibration fatigue analysis method valid verification of thin-walled structure under high temperature environment[J]. Journal of Propulsion Technology, 2018, 39(6):1386-1395(in Chinese).
[17] SHA Y D, GAO Z J, XU F, et al. Influence of thermal loading on the dynamic response of thin-walled structure under thermo-acoustic loading[J]. Advanced Engineering Forum, 2011, 2(3):876-881.
[18] 沙云东, 郭小鹏, 张军. 基于应力概率密度和功率谱密度法的随机声疲劳寿命预估方法研究[J]. 振动与冲击, 2010, 29(1):162-165. SHA Y D, GUO X P, ZHANG J. Random sonic fatigue life prediction based on stress probability density and power spectral density method[J].Journal of Vibration and Shock,2010, 29(1):162-165(in Chinese).
[19] 沙云东,王建,赵奉同,等. 热声载荷下薄壁结构振动响应试验验证与疲劳分析[J]. 航空动力学报,2017, 32(11):2659-2671. SHA Y D, WANG J, ZHAO F T, et al. Vibration response experimental verification and fatigue analysis of thin-walled structures to thermal-acoustic loads[J]. Journal of Aerospace Power, 2017, 32(11):2659-2671(in Chinese).
[20] SHA Y D, WEI J, GAO Z J. Nonlinear response with snap-through and fatigue life prediction for panels to thermo-acoustic loadings[J]. Journal of Vibration and Control, 2014, 20(5):679-697.
[21] 诺顿M P. 工程噪声和振动分析基础[M].盛元生, 顾伟豪, 韩建民,等,译. 北京:航空工业出版社,1993. NORTON M P.Fundamentals of noise and vibration analysis for engineers[M].SHENG Y S,GU W H,HAN J M,et al,translated.Beijing:Aviation Industry Press,1993(in Chinese).
[22] 过玉卿, 龙靖宇. 改进雨流计数法及其统计处理程序[J]. 武汉科技大学学报(自然科学版),1987, 1:22-28. GUO Y Q, LONG J Y. Improved rain flow counting method and statistical processing program[J]. Journal of Wuhan University of Science and Technology (Natural Science edition),1987, 1:22-28(in Chinese).
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