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Composite ceramics thermal barrier coatings of yttria stabilized zirconia for aero-engines

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Journal of Materials Science & Technology 2019年第12期35卷 2814-2823页

作者： Qiaomu Liu Shunzhou Huang Aijie He AECC Sichuan Gas Turbine Establishment

Composite ceramics thermal barrier coatings(TBCs) are widely used in the aero-engines field due to their excellent thermal insulation, which improves the service life and durability of the inherent hot components. The most typical, successful and widely used TBCs material is yttria stabilized zirconia(YSZ). In this paper, fabrication methods, coating structures, materials, failure mechanism and major challenges of YSZ TBCs are introduced and reviewed. The research tendency is put forward as well. This review provides a good understanding of the YSZ TBCs and inspires researchers to discover versatile ideas to improve the TBCs systems.

关键词： Composite ceramics Thermal barrier coatings aero-engine Yttria stabilized zirconia Phase stability Thermal conductivity Failure mechanism

Machining the Integral Impeller and Blisk of aero-engines:A Review of Surface Finishing and Strengthening Technologies

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Chinese Journal of Mechanical engineering 2017年第3期30卷 528-543页

作者： Youzhi Fu Hang Gao Xuanping Wang Dongming Guo key laboratory for precision and non-traditional machining technology of ministry of education dalian university of technologyDalian 116024China

The integral impeller and blisk of an aero-engine are high performance parts with complex structure and made of difficult-to-cut materials. The blade surfaces of the integral impeller and blisk are functional surfaces for power transmission, and their surface integrity has signif- icant effects on the aerodynamic efficiency and service life of an aero-engine. Thus, it is indispensable to finish and strengthen the blades before use. This paper presents a comprehensive literature review of studies on finishing and strengthening technologies for the impeller and blisk of aero-engines. The review includes independent and inte- grated finishing and strengthening technologies and dis- cusses advanced rotational abrasive flow machining with back-pressure used for finishing the integral impeller and blisk. A brief assessment of future research problems and directions is also presented.

关键词： Integral impeller and blisk aero-engine Surface integrity Surface finishing Surface strengthening

Heat transfer characteristics in a narrow confined channel with discrete impingement cooling

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Chinese Journal of aeronautics 2022年第4期35卷 220-229页

作者： Yang LI Tao LIU Jianjun TAO Weihua YANG Likun DONG Hunan Key Laboratory of Turbomachinery on Small and Medium aero-engine AECC Hunan Aviation Powerplant Research InstituteZhuzhou 412002China College of Energy and Power engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Heat transfer characteristics in a narrow confined channel with discrete impingement cooling were investigated using thermal infrared camera. Detailed heat transfer distributions and comparisons on three surfaces with three impact diameters were experimentally studied in the range of Reynolds number of 3000 to 30000. The experimental results indicated that the strong impingement jet leaded to a high strength heat transfer zone in the ΔX=±2.5D;range of the impact center,which was 1.3–2.5 times of the average heat transfer value of the impingement wall. With the same coolant mass flow rate, small diameter case had lower heat transfer coefficient on both inner wall and outside wall, while the impingement wall was insensitive to the impact diameter. The surface averaged Nusselt number of inner wall was only 43%–57% of impingement wall, while the outside wall can reach up to 80%–90%. The larger the diameter, the higher heat transfer enhancement and the smaller the channel flow resistance was observed in term of Reynolds number. The surface averaged Nusselt numbers were developed as the function of Reynolds number and the impingement height-to-diameter for further engineering applications.

关键词： aero-engine Heat transfer characteristics Impingement cooling Narrow confined channel Turbine blade

Recognition and practice on remanufacturing engineering management of military aero-engines

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engineering Sciences 2014年第3期12卷 27-35页

作者： Xiang Qiao Chengdu Holy Industry & Commerce Corp. Ltd. Pengzhou Sichuan 611936 China

The technologies of design, manufacture and MRO （maintenance, repair and overhaul） tor the mili- tary aero-engines, particularly for the fighters, are much more difficult to be mastered than those for any other aero-engines. They have been monopolized by only a few countries and the core technologies have never been transferred due to high risk, high investment, high barrier and high cost. Therefore, our country has long relied on mapping and copying the others＇ engines to satisfy the domestic demand due to not having our own indepen- dent technologies for the design and manufacture of military aero-engines. However, through over 20 years of unremitting effort, the independent MRO has been achieved for all the Chinese fighter engines, covering in- R＆D （research and development） and in-service engines; and the MRO technologies, capabilities, quality, cost-efficiency have reached or exceeded those of original manufacturers. It has grown out of nothing, and then from weak to strong. In particular, dozens of projects concerning the R＆D and engineering application of re- manufacturing have obtained the independent intellectual property rights and are playing an irreplaceable role in achieving leaping improvement of independent MRO for Chinese military aero-engines.

关键词： military aero-engine remanufacturing engineering management

Interval analysis of rotor dynamic response based on Chebyshev polynomials

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Chinese Journal of aeronautics 2020年第9期33卷 2342-2356页

作者： Yanhong MA Yongfeng WANG Cun WANG Jie HONG School of Energy and Power engineering Beihang UniversityBeijing 100083China Collaborative Innovation Center of Advanced aero-engine Beijing 100083China

Uncertainty is extensively involved in the rotor systems of rotating machinery, which may cause an unstable vibrational response. To take the uncertainty into consideration for the uncertain rotor-bearing system, an improved unified interval analysis method based on the Chebyshev expansion is established in this paper. Firstly, the Chebyshev Interval Method(CIM) to calculate not only the critical speeds but also the dynamic response of rotor with uncertain parameters is introduced. Then, the numerical investigation is carried out based on the developed double disk rotor model and computation procedure, and the results demonstrate the validity. But when the uncertainty is sufficiently large to influence critical speeds, the upper and lower bounds are far from the actual bounds. In order to overcome the defects, a Bound Correction Interval analysis Method(BCIM) is proposed based on the Chebyshev expansion and the modal superposition. In use of the improved method, the bounds of the interval responses, especially the upper bound,are corrected, and the comparison with other methods demonstrates that the higher accuracy and a wider application range.

关键词： aero-engine Chebyshev expansion Interval analysis methods Rotor dynamics Uncertainty

Time Sequence Change-Point Model of Electrostatic State Parameters of Aircraft engine

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Transactions of Nanjing University of aeronautics and Astronautics 2018年第1期35卷 126-134页

作者： Fu Yu Wei Dongdong Zuo Hongfu Feng Zhengxing College of aeronautical engineering Civil Aviation University of China College of Civil Aviation Nanjing University of Aeronautics and Astronautics

Electrostatic monitoring technology of particle charging information can facilitate online monitoring of aero-engine,which effectively enhances engine fault diagnosis and health *** traditional engine state monitoring technologies,aircraft engine monitoring by gas path electrostatic monitoring not only covers the predicted information source itself,but also detects the information that can provide an early warnings for initial fault states through gas path charging *** paper establishes a non-stationary time sequence change-point model for anomaly recognition of electrostatic signals based on change-point theory combined with difference method of non-stationary time ***,electrostatic induction data were utilized by the engine life test for a particular aircraft to validate the proposed *** results indicate that the activity level and the event rate were0.5—0.8(nc)and 50%,respectively,which were far greater than 4—12(pc)and 0—4% under normal working conditions of the engine.

关键词： aero-engine state identification electrostatic monitoring technology time series change-point statistics

Experimental Study of the Vibration Phenomenon of Compressor Rotor Blade Induced by Inlet Probe Support

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Journal of Thermal Science 2021年第5期30卷 1674-1683页

作者： YANG Yong XIANG Honghui GAO Jie XU Kaijun YANG Rongfei GE Ning Department of Flight Technology Civil Aviation Flight University of ChinaGuanghan618307China AECC Sichuan Gas Turbine Establishment Mianyang621000China College of Energy and Power engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China

An experimental investigation was conducted in order to understand the installation effects of inlet measurement probes on the vibration characteristics of the rotor blades in two axial *** vibration signal of the rotor blades was analyzed for different layouts of the inlet measurement *** the three-stage axial compressor,the first-order resonance occurs on the first stage of the rotor blades at an engine order excitation condition,which is induced by the cylindrical probe support with a diameter of 10 *** the size of the probe support is decreased,the vibration level reduces *** contrast,for the six-stage axial compressor,the first-order resonance occurs on the first stage of the rotor blades at an excitation source of 6th order,which is triggered by the inlet measurement probes and the upstream *** the number of the inlet measurement probes is changed,the resonance of the rotor blades vanishes.

关键词： aero-engine axial compressor probe support rotor blade vibration strain resonance

Integral inference method for da/dN-ΔK and P-da/dN-ΔK curves

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航空动力学报 2011年第6期26卷 1251-1256页

作者： FU Hui-min WU Qiong Research Center of Small Sample Technology Beijing University o~ Aeronautics and Astronautics Beijing 100191 China

The integral inference method for fatigue crack growth(FCG) curve was established based on the two-variance regression *** estimates of da/dN-ΔK curve and P-da/dN-ΔK curve with high confidence level and high survival probability were also *** data scatter with stress intensity factor ranges in reality,which limits the group test method's *** presented method analyzes FCG curve as an integration,thus it can exploit the lengthwise information among the FCG rates corresponding to different stress intensity factor ***,compared with group test method,the presented method can not only save specimens,but also have higher precision in the evaluations of da/dN-ΔK and P-da/dN-ΔK curves.

关键词： aero-engine fatigue crack growth(FCG) crack growth rate integral estimate reliability

Nonlinear interval analysis of rotor response with joints under uncertainties

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Chinese Journal of aeronautics 2020年第1期33卷 205-218页

The dynamic influence of joints in aero-engine rotor systems is investigated in this ***,the tangential stiffness and loss factor are obtained from an isolated lap joint setup with dynamic excitation ***,the influence of the normal contact pressure and the excitation level are examined,which revel the uncertainty in ***,the updated Thin Layer Elements(TLEs)method with fitted parameters based on the experiments is established to simulate the dynamic properties of joints on the *** response of the rotor subjected to unbalance excitation is calculated,and the results illustrate the effectiveness of the proposed ***,using the Chebyshev inclusion function and a direct iteration algorithm,a nonlinear interval analysis method is established to consider the uncertainty of parameters in *** accuracy is proved by comparison with results obtained using the Monte-Carlo *** with the updated TLEs,the nonlinear Chebyshev method is successfully applied on a finite model of a *** study shows that substantial attention should be paid to the dynamical design for the joint in rotor systems,the dynamic properties of joints under complex loading and the corresponding interval analysis method need to be intensively studied.

关键词： aero-engine Bolted joints Nonlinear interval analysis method Rotor dynamics Uncertainties Updated Thin Layer Elements(TLE)method