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Influence Factors for Impact Actions and Transient Trajectories of Fan Blades after Fan Blade Out in Typical 2-Shaft High Bypass Ratio Turbofan engine

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Journal of Thermal Science 2022年第1期31卷 96-110页

作者： XU Xue LI Hongxin FENG Guoquan shenyang engine Research institute Aero Engine Corporation of ChinaShenyang 110015China corporation Headquarter Aero Engine Corporation of ChinaBeijing 100097China

To enhance the understanding of design characters, which have prominent influences during the fan blade out event, a simplified geometrical and dynamic analysis method was derived, and a typical 2-shaft high bypass ratio turbofan engine was selected and modeled. Based on analytical deriving and engineering experience learned from the real engine failure case, three determinative impact actions were recognized from the fan blade out process. The transient trajectories of these impact actions were researched in analytical method, and then thickness of acoustic lining, quantity of fan blades and threshold load of structural fuse were analyzed as key design characters. 36 serialized fan blade out transient dynamic simulations were conducted by using the 2-shaft high bypass ratio turbofan engine model within different combinations of the three key design factors. The results from geometrical and dynamic analysis matched mainly well with the results from simulations. Characteristic phenomenon in simulation can be explained theoretically. Five conclusions can be summarized from these results. (1) If thickness fan acoustic lining was thinner, the deviation between simplified analytical calculation and simulation were not outstanding to predict Blade-Casing the first impact time and angular position. (2) An appropriate thickness of acoustic lining could make a lower impact stress of fan casing at the first impact. (3) Different thickness of acoustic linings leaded to two impact modes for blade 2, which were tip impact and root impact. (4) Different impact conditions between blade 1 and blade 2 caused remarkable speed components distinction of blade 1, and leaded to a wide range of transient trajectory of blade 1 during FBO event. (5) Thicker acoustic lining in this research can usually find the porper threshold loads setting, which can give a satisfactory outbound vibration. Two details were raised for further research, which were impact behavior of composite material fan bl

关键词： fan blade out transient trajectory design character structural fuse high bypass ratio turbofan

Review of Numerical Simulation of TGO Growth in Thermal Barrier Coatings

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Computer Modeling in engineering & Sciences 2022年第8期132卷 361-391页

作者： Quan Wen Fulei Jing Changxian Zhang Shibai Tang Junjie Yang aero engine Academy of china Aero Engine(Group)Corporation of ChinaBeijing101304China institute for aero engine Tsinghua UniversityBeijing100084China

Thermally grown oxide(TGO)is a critical factor for the service life of thermal barrier coatings(TBC).Numerical simulations of the growth process of TGO have become an effective means of comprehensively understanding the progressive damage of the TBC *** present,technologies of numerical simulation to TGO growth include two categories:coupled chemical-mechanical methods and mechanical equivalent *** former is based on the diffusion analysis of oxidizing elements,which can describe the influence of bond coat(BC)consumption and phase transformation in the growth process of TGO on the mechanical behavior of each layer of TBC,and has high accuracy for the thickness evolution of TGO,but they cannot describe the lateral growth of TGO and the rumpling phenomenon *** latter focuses on describing the final stress and strain state after the growth of a specific TGO rather than the complete growth processes of *** on the measured TGO thickness growth curve,simulations of thickening and lateral growth can be achieved by directly applying anisotropic volumetric strain to oxidized elements and switching elements properties from the BC to the TGO.

关键词： Thermal grown oxide(TGO) numerical simulation thermal barriers coatings(TBC) finite element method lateral growth

Development of a deviation package method for low-cost robust optimization in compressor blade design

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Chinese Journal of aeronautics 2024年第4期37卷 166-180页

作者： Mingzhi LI Xianjun YU Dejun MENG Guangfeng AN Baojie LIU Research institute of aero-engine Beihang UniversityBeijing 100191China National Key Laboratory of Science&Technology on aero-engine aero-Thermodynamics Beihang UniversityBeijing 100191China AECC shenyang engine Research institute Shenyang 110015China

Manufacture variations can greatly increase the performance variability of compressor blades. Current robust design optimization methods have a critical role in reducing the adverse impact of the variations, but can be affected by errors if the assumptions of the deviation models and distribution parameters are inaccurate. A new approach for robust design optimization without the employment of the deviation models is proposed. The deviation package method and the interval estimation method are exploited in this new approach. Simultaneously, a stratified strategy is used to reduce the computational cost and assure the optimization accuracy. The test case employed for this study is a typical transonic compressor blade profile, which resembles most of the manufacture features of modern compressor blades. A set of 96 newly manufactured blades was measured using a coordinate measurement machine to obtain the manufacture variations and produce a deviation package. The optimization results show that the scatter of the aerodynamic performance for the optimal robust design is 20% less than the baseline value. By comparing the optimization results obtained from the deviation package method with those obtained from widely-used methods employing the deviation model, the efficiency and accuracy of the deviation package method are demonstrated. Finally, the physical mechanisms that control the robustness of different designs were further investigated, and some statistical laws of robust design were extracted.

关键词： Manufacture variations Robust design optimization Compressor leading edge aerodynamics Physical mechanism

Breaking the geometry-performance tradeoff in compressor deviation modeling:Nested principal component analysis

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Chinese Journal of aeronautics 2024年第9期37卷 131-149页

Uncertainties in the aerodynamic performance of compressors,introduced by manufacturing variations,have received more and more attentions in recent *** deviation model plays a crucial role in evaluating this uncertainty and facilitating robust ***,current deviation models with a few variables cannot simultaneously achieve a precise geometric approximation of deviation and provide an accurate assessment of performance *** paper introduces a novel deviation modeling method named Nested Principal Component Analysis(NPCA)to break this *** this method,both geometry-based and performance-based modes are utilized to describe manufacturing *** considering aerodynamic sensitivity,surface deformations that significantly impact aerodynamic performance can be extracted for deviation *** demonstrate the superiority of this newly proposed method,ninety-eight newly manufactured compressor rotor blades were measured using a coordinate measurement machine,and both NPCA and Principal Component Analysis(PCA)were employed to model the real manufacturing *** results indicate that,in comparison to the PCA method,the NPCA method achieves an equivalent level of accuracy in geometric reconstruction and evaluation of mean ***,the same level of accuracy can be obtained with eight NPCA modes and fifty PCA modes when assessing the scatter in aerodynamic ***,the working mechanism of the NPCA method for accurate uncertainty quantification was further investigated.

关键词： Manufacturing variation Uncertainty quantification Dimension reduction aerodynamics Flow mechanism

Stress-controlled LCF experiments and ratcheting behaviour simulation of a nickel-based single crystal superalloy with [001] orientation

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Chinese Journal of aeronautics 2021年第8期34卷 112-121页

作者： Bin ZHANG Rongqiao WANG Dianyin HU Kanghe JIANG Jianxing MAO Fulei JING Xinyi HAO School of Energy Power EngineeringBeihang UniversityBeijing 100083China Beijing Key Laboratory of aero-engine Structure and Strength Beijing 100083China Research institute of aero-engine Beihang UniversityBeijing 100083China Hunan Aviation Powerplant Research institute Aero Engine(Group)Corporation of ChinaZhuzhou 412002China aero engine Academy of china Aero Engine(Group)Corporation of ChinaBeijing 101304China

Uniaxial ratcheting behaviour and low cycle fatigue(LCF)failure mechanism of nickel-based single crystal superalloy DD6 with[001]orientation are investigated through the stresscontrolled LCF tests with stress ratio *** the deformation behaviour during the wholelifetime from the beginning of the experiment to the fracture of the specimen,as well as the fractographic/metallographic morphology,are compared with the strain-controlled LCF experimental *** the scanning electron microscope(SEM)observations,it is shown that the failure characteristics under stress-controlled LCF loading are similar with those under strain-controlled ***,unlike strain-controlled LCF loading,even under fully reversed cycle loading for stress-controlled LCF,DD6 shows significant ratcheting behaviour due to the tensioncompression *** addition,the LCF lifetimes under stress control are significantly shorter than the LCF lifetimes under strain control,and the culprit might be the detrimental effect of ratcheting strain on LCF *** on these phenomena,an improved crystal plasticity constitutive model on the basis of slip-based Walker constitutive model is developed through modifying the kinematic hardening rule in order to overcome the inaccurate prediction of decelerating stageand stable stage of ratcheting ***,combining the continuum damage mechanics,a damage-coupled crystal plasticity constitutive model is proposed to reflect the damage behaviour of DD6 and the accelerating stage of ratcheting *** simulation results for the stress-controlled LCF deformation behaviour including the whole-lifetime ratcheting behaviour show good agreement with the experimental data.

关键词： Crystal plasticity constitutive model Low cycle fatigue Nickel-based single crystal superalloy Ratcheting behaviour Stress-controlled experiment

Large eddy simulation of turbulent premixed piloted flame using artificial thickened flame model coupled with tabulated chemistry

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Applied Mathematics and Mechanics(English Edition) 2018年第9期39卷 1277-1294页

作者： Zhou YU Hongda ZHANG Taohong YE Minming ZHU Department of Thermal Science and Energy engineering University of Science and Technology of China shenyang engine Research institute Aero Engine (Group) Corporation of China

A sub-grid scale(SGS) combustion model, which combines the artificial thickened flame(ATF) model with the flamelet generated manifold(FGM) tabulation method, is proposed. Based on the analysis of laminar flame structures, two self-contained flame sensors are used to track the diffusion and reaction processes with different spatial scales in the flame front, respectively. The dynamic formulation for the proposed SGS combustion model is also performed. Large eddy simulations(LESs) of Bunsen flame F3 are used to evaluate the different SGS combustion models. The results show that the proposed SGS model has the ability in predicting the distributions of temperature and velocity reasonably, while the predictions for the distributions of some species need further improvement. The snapshots of instantaneous normalized progress variables reveal that the flame is more remarkably and severely wrinkled at the flame tip for flame *** satisfactory results obtained by the dynamic model indicate that it can preserve the premixed flame propagation characteristics better.

关键词： large eddy simulation(LES) artificial thickened flame model tabulation dynamic modeling flame sensor

Large eddy simulation of turbulent premixed and stratified combustion using flame surface density model coupled with tabulation method

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Applied Mathematics and Mechanics(English Edition) 2018年第12期39卷 1719-1736页

Large eddy simulations(LESs) are performed to investigate the Cambridge premixed and stratified flames, SwB1 and SwB5, respectively. The flame surface density(FSD) model incorporated with two different wrinkling factor models, i.e., the Muppala and Charlette2 wrinkling factor models, is used to describe combustion/turbulence interaction, and the flamelet generated manifolds(FGM) method is employed to determine major scalars. This coupled sub-grid scale(SGS) combustion model is named as the FSD-FGM model. The FGM method can provide the detailed species in the flame which cannot be obtained from the origin FSD model. The LES results show that the FSD-FGM model has the ability of describing flame propagation, especially for stratified flames. The Charlette2 wrinkling factor model performs better than the Muppala wrinkling factor model in predicting the flame surface area change by the *** combustion characteristics are analyzed in detail by the flame index and probability distributions of the equivalence ratio and the orientation angle, which confirms that for the investigated stratified flame, the dominant combustion modes in the upstream and downstream regions are the premixed mode and the back-supported mode, respectively.

关键词： large eddy simulation(LES) flame surface density(FSD) model tabulation premixed combustion stratified combustion

Designing method of acceleration and deceleration control schedule for variable cycle engine

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Chinese Journal of aeronautics 2021年第5期34卷 27-38页

作者： Linyuan JIA Yuchun CHEN Ronghui CHENG Tian TAN Reran SONG School of Power and Energy Northwestern Poly technical UniversityXi'an 710072China aero-engine corporation of china Shenyang Engine Research InstituteShenyang 110066China

Studies show that different geometries of a Variable Cycle engine(VCE)can be adjusted during the transient stage of the engine operation to improve the engine ***,this improvement increases the complexity of the acceleration and deceleration control *** order to resolve this problem,the Transient-state Reverse Method(TRM)is established in the present study based on the Steady-state Reverse Method(SRM)and the Virtual Power Extraction Method(VPEM).The state factors in the component-based engine performance models are replaced by variable geometry parameters to establish the TRM for a double bypass *** results are compared with the conventional component-based model from different aspects,including the accuracy and the convergence *** TRM is then employed to optimize the control schedule of a *** results show that the accuracy and the convergence rate of the proposed method are consistent with that of the conventional *** the other hand,it is found that the new-model-optimized control schedules reduce the acceleration and deceleration time by 45%and 54%,***,the surge margin of compressors,fuel–air ratio and the turbine inlet temperature maintained are within the acceptable *** is concluded that the proposed TRM is a powerful method to design the acceleration and deceleration control schedule of the VCE.

关键词： Acceleration and deceleration Control schedule optimization Steady-state reverse method Transient-state reverse method Variable cycle engine Virtual power extraction method

Performance evaluation of creep feed grinding ofγ-TiAl intermetallics with electroplated diamond wheels

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Chinese Journal of aeronautics 2021年第6期34卷 100-109页

作者： Xinxin XI Wenfeng DING Zhixin WU Lama ANGGEI College of Mechanical and Electrical engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China shenyang Liming aero-engine Co. Ltd.Aero-Engine Corporation of ChinaShenyang 110043China

This paper evaluates the performance of creep feed grindingγ-TiAl intermetallic(Ti-45 Al-2 Mn-2 Nb)using electroplated diamond ***,a comparative analysis with the grinding results by using electroplated CBN wheels was conducted,mainly involving abrasive wheel wear behavior and maximum material removal rate below surface burn *** was found that the diamond wheel would produce much better grinding results including lower wheel wear rate and higher maximum material removal *** the surface integrity obtained at different level of material removal rate was characterized with the utilization of the diamond *** poor ductility of thisγ-TiAl intermetallic material was found to have a marginal effect on the surface integrity,as no severe surface defects such as material pullout were generated during the stable wheel wear *** the involved operating parameters,a deformation layer was produced with~10μm or more in thickness depending on the material removal rate ***,a work-hardened layer extending to more than 100μm was produced with a maximum microhardness of above 520 HV0.05(bulk value 360 HV0.05).The residual stress remained compressive,with a value of above-100 MPa and even up to-500 MPa for an elevated material removal *** chip was the main chip type,indicating good wheel sharpness in the grinding process.

关键词： Creep feed grinding Electroplated abrasive wheels Surface integrity Wheel wear γ-TiAl intermetallic