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Chinese Journal of Aeronautics 2020年第2期33卷 598-608页

作者： Jian WANG fengtong zhao Yundong SHA Song GU Department of Aircraft Maintenance Engineering Chengdu Aeronautic PolytechnicChengdu 610100China Liaoning Key Laboratory of Advanced Test Technology for Aeronautical Propulsion System Shenyang Aerospace UniversityShenyang 110136China

Rapid alternating stress is formed in structure subjected to harsh thermal-acoustic loads,which will affect fatigue performance and reduce fatigue life ***,fatigue experiment of superalloy thin-walled structure was carried out to obtain fatigue damage location and failure time of the experiment specimen,and S-iN curves of superalloy thin-walled structure at 723 K were ***,dynamic response simulation of superalloy thin-walled structure under the same load as experiment was implemented,and fatigue life was estimated based on the fatigue life prediction model which mainly included:improved rain-flow counting method,Morrow average stress model and Miner linear cumulative damage ***,comparisons between simulation solutions and experimental results achieved a consistency,which verified the validity of the Fatigue Life Prediction Model(FLPM).Moreover,taking a rectangle plate as the analysis object,the distributions of Fain-low circulation blocks and damage levels of the structure were discussed ***,current research indicates that in pre-buckling the structure is in softened area and fatigue life decreases with the increase of temperature;in post-buckling the structure is in hardened area and fatigue life increases with the increase of temperature within a certain range.

关键词： Experimental verification Fatigue life Improved rain-flow counting method Rain-flow cycle matrix Rain-flow damage matrix Thermal-acoustic load Thin-walled structures

Physical model for acoustic resonance in annular cavity structure

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Chinese Journal of Aeronautics 2020年第12期33卷 3228-3237页

作者： fengtong zhao Mingsui YANG Xiaodong JING Deyou WANG Yundong SHA Yujin LIU School of Energy and Power Engineering Beihang UniversityBeijing 100083China Liaoning Province Key Laboratory of Advanced Measurement and Test Technology of Aviation Propulsion Systems Shenyang Aerospace UniversityShenyang 110136China Shenyang Engine Research Institute of AECC Shenyang 110015China

A physical model for acoustic resonance in the annular cavity structure is developed to represent the typical characteristic when acoustic resonance ***,the measurement of sound pressure in the casing and rotor blades vibration is operated in a multistage high pressure *** sharp peak frequency and discrete multi-tone occur in the frequency spectrum of sound pressure in the compressor,and the vibration of the first stage of rotor blades synchronously presents the high *** frequencies associated with rotor blades vibration can be calculated with rotating sound source *** is also confirmed that acoustic resonance occurs in the multistage *** acoustic similarity principle,an annular cavity model is established to simulate the typical characteristics of acoustic resonance in the compressor based on Large Eddy Simulation(LES)and Lighthill acoustic *** coupling relationship between cavity acoustic mode and disc vibration mode shape is expounded when acoustic resonance occurs in the *** acoustic resonance will be locked in the certain flow rate *** these characteristics match well with those occur in the multistage high pressure compressor.

关键词： Acoustic resonance Annular cavity structure Large eddy simulation Lighthill acoustic analogy Multistage compressor

Experimental study of rotor blades vibration and noise in multistage high pressure compressor and their relevance

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Chinese Journal of Aeronautics 2020年第3期33卷 870-878页

作者： fengtong zhao Xiaodong JING Mingsui YANG Deyou WANG Yundong SHA Xiaochi LUAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Liaoning Province Key Laboratory of Advanced Measurement And Test Technology of Aviation Propulsion Systems Shenyang Aerospace UniversityShenyang 110136China Shenyang Engine Design and Research Institute Aero Engine(Group)Corporation of ChinaShenyang 110015China

Rotor blades fault of aeroengine compressor is mostly caused by mechanical and aerodynamic *** the excitation factor of high intensity sound wave to rotor blades should not be *** researches are conducted on a multistage high pressure *** high level vibration occurs on the first stage of rotor blades, the noise spectrum presents typical characteristic for discrete multi-tone in the *** amplitude of blade vibration displacement and the sound pressure level of characteristic frequency noise increases and decreases simultaneously and reaches the maximum value at the same *** frequency merely occur on a certain speed range and is locked in a specific range which presents no variation with the rotating *** high level vibration occurs on the first stage of rotor blades, the noise spectrum presents a sharp peak and the propagation state of the characteristic frequency is a helix structure in the *** can be confirmed that acoustic resonance occurs in the multistage *** acoustic resonance frequency and its side band frequencies are generated by modulation of a rotating noise source at the rotor speed which is the excitation source of the rotor blades vibration.

关键词： Acoustic resonance Blades vibration Characteristic frequency Multistage compressor Source identification

Dynamic recrystallization and phase transformation behavior of a wrought β-γ TiAl alloy during hot compression

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Progress in Natural Science:Materials International 2020年第4期30卷 517-525页

作者： Lei Zhu Jinshan Li Bin Tang fengtong zhao Ke Hua Shaopeng Yan Hongchao Kou State Key Laboratory of Solidification Processing Northwestern Polytechnical University Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Northwestern Polytechnical University

The dynamic recrystallization(DRX) and phase transformation(PT) behavior of a wrought β-γ TiAl alloy during hot compression under various deformation temperatures were investigated. The typical work hardening and flow softening features indicated that DRX was the dominating softening mechanism. Both γ-DRX and β-DRX took place during the hot compression. γ-DRX was triggered at all compression temperatures, while the β-DRX was induced when the compression temperature was above 1000 °C. The hot deformation kinetics was calculated, which showed that DRX behavior existed in the whole hot compression process, and the DRX volume fraction increased with the increase of the compression temperature. Combined with the microstructure observation, it concluded that the β/B2+α2→γ PT occurred at 850 °C and 1000 °C, while the γ→β/B2 PT happened at 1050 °C during hot compression, which is important to optimize microstructure. Moreover, the hot compression mechanism changed from dislocation gliding to grain-boundary sliding was discussed.

关键词： β-γ TiAl alloy Hot compression Dynamic recrystallization Microstructure Phase transformation

Address at the Opening Ceremony of Beijing Forum 2008

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Address at the Opening Ceremony of Beijing Forum 2008

Speech at the Opening Ceremony of Beijing Forum 2006

文明的和谐与共同繁荣：文明的普遍价值和发展趋向——北京论坛（2008）

作者： zhao fengtong Vice Mayor,Beijing Municipal Government

Distinguished guests, Ladies and Gentlemen, Good morning. Today,scholars of humanities and social sciences are gathering in Beijing once again to attend Beijing Forum 2008,an annual grand academic assembly of humanities and social *** on behalf of Beijing municipal government and CPC Beijing Municipal Committee,I would like

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Speech at the Opening Ceremony of Beijing Forum 2006

热声载荷下薄壁结构振动响应试验验证与疲劳分析

文明的和谐与共同繁荣：对人类文明方式的思考——北京论坛（2006）

作者： zhao fengtong Vice Mayor,Beijing Municipal Government

Distinguished guests, ladies and gentlemen, It is with great pleasure to have you,distinguished guests,with us to witness this grand opening of the Beijing Forum 2006 in Beijing’ s most beautiful *** of all,on behalf of His Honor *** Qishan,I would like to extend to you,the warmest congratulations from the Beijing

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航空动力学报 2017年第11期32卷 2659-2671页

作者：沙云东王建赵奉同骆丽沈阳航空航天大学航空航天工程学部辽宁省航空推进系统先进测试技术重点实验室沈阳110136

由于热声环境下金属薄壁结构表现出复杂的大挠度强非线性振动响应特性,影响结构的疲劳性能与寿命,结合有限元法与降阶模态法对四边固支高温合金矩形薄壁结构的热声响应进行计算。结果研究发现:屈曲后结构出现跳变运动且应力循环呈三角... 详细信息

由于热声环境下金属薄壁结构表现出复杂的大挠度强非线性振动响应特性,影响结构的疲劳性能与寿命,结合有限元法与降阶模态法对四边固支高温合金矩形薄壁结构的热声响应进行计算。结果研究发现:屈曲后结构出现跳变运动且应力循环呈三角状分布,热声载荷的相对强弱决定了跳变形式。采用改进雨流计数法、Morrow平均应力模型、Miner线性损伤累积理论计算热声疲劳寿命,屈曲前到临界屈曲时应力循环损伤量级显著增大,由10-5增大到10-4,寿命随温度增加呈先减小后增加趋势。开展薄壁结构热声试验,并将仿真计算结果与试验结果进行对比,结果表明结构的模态频率偏差不超过1Hz,动态应变响应结果的量值相当,验证了薄壁结构热声响应计算方法与模型的有效性。

关键词：热声载荷非线性振动响应疲劳寿命屈曲跳变试验验证

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薄壁结构高温随机振动疲劳寿命估算方法

振动与冲击 2020年第2期39卷 64-71,85页

作者：沙云东朱付磊赵奉同张墨涵沈阳航空航天大学宁省航空推进系统先进测试技术重点实验室沈阳110136 北京航空航天大学能源与动力工程学院北京100191

为了研究涡轮转子叶片在高温环境中气流激振力作用下随机振动疲劳失效机理,从基础研究出发,采用薄壁板件为研究对象。基于高温试验台与振动台联合试验,结合数值仿真,得到了不同温度和不同振动量级组合下试验件根部与颈部的轴向动应力响... 详细信息

为了研究涡轮转子叶片在高温环境中气流激振力作用下随机振动疲劳失效机理,从基础研究出发,采用薄壁板件为研究对象。基于高温试验台与振动台联合试验,结合数值仿真,得到了不同温度和不同振动量级组合下试验件根部与颈部的轴向动应力响应规律。基于疲劳累积损伤理论,采用改进的雨流计数法预估试验件的疲劳寿命。通过高温随机振动试验,同时参照常温随机振动试验,获得试验件在实际工况下的应力、应变、频率等动力学响应和寿命数据,并对各个试验组的响应与寿命进行数据统计,仿真与试验结果比较发现:数值仿真对试验件破坏位置判断准确,应力响应误差在5.6%以内,频率响应相差1%左右,疲劳寿命相差28.6%以内,证明了高温条件下随机振动疲劳分析方法是有效的而且精确的。

关键词：薄壁板高温条件随机振动疲劳寿命试验验证

热声载荷作用下薄壁结构非线性响应分析和试验验证

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航空学报 2019年第4期40卷 198-209页

作者：沙云东张墨涵赵奉同朱付磊沈阳航空航天大学辽宁省航空推进系统先进测试技术重点实验室沈阳110136 北京航空航天大学能源与动力工程学院北京100083

针对热声载荷作用下薄壁结构大挠度非线性响应问题,开展了固支约束金属薄壁板结构热声激励试验及数值模拟分析。通过计算结果与试验结果对比,表明两者结果存在一致性,进而验证了薄壁板在热声载荷作用下动态响应计算方法和数值模型的有... 详细信息

针对热声载荷作用下薄壁结构大挠度非线性响应问题,开展了固支约束金属薄壁板结构热声激励试验及数值模拟分析。通过计算结果与试验结果对比,表明两者结果存在一致性,进而验证了薄壁板在热声载荷作用下动态响应计算方法和数值模型的有效性。在此基础上,针对加筋板结构完成了多种热声载荷组合作用下的动力学响应计算,获得了时域位移响应。重点对该结构在后屈曲状态下的3种典型振动形式进行分析,总结出热载荷与声载荷之间的相对强度决定了板的不同跳变形式。采用统计分析方法建立了位移响应的概率谱密度函数(PDF)并绘图,清楚地显示了后屈曲板的PDF表现出双峰现象。使用功率谱密度(PSD)函数分析了响应频率和峰值随着温度升高的变化,并确定了板的软化和硬化区域。总结了屈曲前/后结构特定区域拉应力和压应力的变化规律,并阐述了造成这种变化的原因。本文工作可对热声载荷作用下薄壁结构响应分析和动强度设计提供参考依据。

关键词：薄壁结构热声载荷非线性响应屈曲跳变试验验证

热声载荷作用下金属薄壁结构的振动响应与试验验证

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振动与冲击 2017年第20期36卷 218-224,232页

作者：沙云东王建骆丽赵奉同贾秋月沈阳航空航天大学辽宁省航空推进系统先进测试技术重点实验室沈阳110136

针对航空航天薄壁结构在热声载荷作用下的非线性振动响应问题,基于声振耦合理论,采用耦合的有限元/边界元法对四边固支高温合金矩形薄壁结构进行了动力学响应计算。重点研究了薄壁结构在行波加载与扩散场加载条件下的振动应力/应变响应... 详细信息

针对航空航天薄壁结构在热声载荷作用下的非线性振动响应问题,基于声振耦合理论,采用耦合的有限元/边界元法对四边固支高温合金矩形薄壁结构进行了动力学响应计算。重点研究了薄壁结构在行波加载与扩散场加载条件下的振动应力/应变响应规律,讨论了温升对结构振动响应的影响规律,分析了薄壁结构热屈曲(Thermal-buckling)和跳变(Snap-through)响应特性。通过将薄壁结构在不同温度条件下的振动模态以及动态应变响应的仿真结果与热环境下的声激振试验结果进行对比,表明计算的基频量值及随温度的变化关系与试验结果获得较好的一致性,计算的应变响应与试验测试结果量值相当,验证了热声响应计算方法与模型的有效性。该研究提出的金属薄壁结构在热声载荷作用下的非线性振动响应计算方法及分析结论对进一步开展热声疲劳寿命预测及动强度设计提供依据。

关键词：金属薄壁结构热声载荷非线性振动响应试验验证