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Extremum selection method of random variable for nonlinear dynamic reliability analysis of turbine blade deformation

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Propulsion and Power Research 2012年第1期1卷 58-63页

作者： Chengwei Fein Guangchen Bai School of Energy and Power Engineering Beihang UniversityBeijing 100191China

To effectively select random variable in nonlinear dynamic reliability analysis,the extremum selection method(ESM)is ***,the basic idea was introduced and the mathematical model was established for the *** nonlinear dynamic reliability analysis of turbine blade radial deformation was taken as an example to verify the *** results show that the analysis precision of the ESM is 99.972%,which is almost kept consistent with that of the Monte Carlo method;moreover,the computing time of the ESM is shorter than that of the traditional ***,it is demonstrated that the ESM is able to save calculation time and improve the computational efficiency while keeping the calculation precision for nonlinear dynamic reliability *** present study provides a method to enhance the nonlinear dynamic reliability analysis in selecting the random variables and offers a way to design structure and machine in future work.

关键词： Extremum selection method(ESM) turbine blade Radial deformation Reliability analysis Random variable Nonlinear Dynamic

A turbine blade Parametric Modeling Method Considering 1-D Heat Transfer Analysis

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Computer Aided Drafting,Design and Manufacturing 2015年第3期25卷 1-9页

作者： LI Ji-xing XI Ping GUO Yan-fei ZHANG Jian-qi School of Mechanical Engineering and Automation Beihang University School of Software Engineering Beihang University School of Mechanical Engineering Northwestern Polytechnical University

Traditional feature-based turbine blade models can match the needs of geometric modeling but could hardly meet the requirement of data extraction in 1-D heat transfer analysis. In this paper, the requirements of data extraction in 1-D heat transfer analysis are taken into consideration as well as geometric representation in parametric design process. An improved turbine blade parametric modeling method is proposed. Based on the modeling method proposed, a system structure of blade modeling process considering 1-D heat transfer analysis is devised. Eventually, a turbine blade parametric modeling system is constructed to test and verify the feasibility of the proposed modeling method and system structure. Experiments show that the blade parametric modeling method proposed can make geometric models better adapt to the specific requirements of 1-D heat transfer analysis and has certain reference value to the creation of high quality digital models.

关键词： turbine blade parametric modeling 1-D heat transfer analysis data extraction

Data Fusion for Combining Techniques to In Situ Detect Defects of turbine blade

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Data Fusion for Combining Techniques to In Situ Detect Defec...

Aerodynamic and Heat Transfer Simulation of Cooling turbine blade with Different Tips

17th World Conference on Non-Destructive Testing

作者： Wugang TIAN Mengchun PAN Feilu LUO Dixiang CHEN Jianbin SU College of Mechatronics Engineering and Automation,National Univ.of Defense Technology,ChangSha,HuNan,China

＜正＞In non-destructive testing （NDT） it is important to have a high probability of detection （POD） and reliable characterization of each *** can be gained by using several techniques,which leads to an increase in cost and time for *** option is to use several techniques combined into a single probe, in which case data fusion for the techniques is possible.A dual probe containing an eddy current probe and a borescope is *** two techniques are complementary,and no detrimental interference is *** dual probe can in situ detect defects of complicated object such as aeroengine,which can reduce the need for costly *** blade is one of crucial parts in aeroengine. Defects of turbine blade would endanger flight *** and corrosion are primary defects of turbine *** and corrosion are detected in situ using eddy current and borescope *** on the Dempster-Shafer （D-S） theory of evidence,a decision level data fusion was used to combine probability mass values from borescope and eddy *** final classification results were obtained by making decisions based on the maximum belief of the fused results. The experimental results show that the high reliable characterization of defect is gained using the data fusion.

关键词： Data fusion Borescope Eddy current testing turbine blade D-S Theory Non-destructive Testing

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Aerodynamic and Heat Transfer Simulation of Cooling Turbine ...

STUDY ON FLOW FIELD OF turbine blade WITH FLEXIBLE 3-ELECTRODE FEEDING METHOD IN ECM

The 2010 International Conference on Manufacturing Science and Materials Engineering(ICMSME 2011)

作者： Kuahai Yu Xi Yang Zhixun Wen Zhufeng Yue School of Schematizing and Architectural Engineering Henan University of Science and Technology School of Material Northwestern Polytechnical University Mechanics Engineering Department Northwestern Polytechnical University

This paper studies the aerodynamic and heat transfer influence of tip structures for cooling turbine blade. Four blades with different tip features are discussed, and coupling aerodynamic and heat transfer method is used to accomplish the simulation. The results show that squealer tip can greatly reduce the heat transfer between tip surface and high temperature gas, and also it reduces tip leakage, to some extent. That’s because it exists obviously eddy near the tip surface. Tip injection holes can cool the tip surface effectively, and it will greatly reduce the temperature of tip surface. However, injection holes improve tip leakage slightly.

关键词： turbine blade blade tip squealer injection holes aerodynamic and heat transfer

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STUDY ON FLOW FIELD OF TURBINE BLADE WITH FLEXIBLE 3-ELECTRO...

Comparative Study on Different Methods for Prediction of Thermal Insulation Performance of Thermal Barrier Coating Used on turbine blades

2006年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： XU Zhengyang, ZHU Di, WANG Lei, SHI Xianchuan College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China

Electrochemical machining (ECM) provides an economicaland effective way for machining heat-resistant, high strengthmaterials into complex shapes which are difficult to machineby conventional methods.

关键词： ECM turbine blade 3-Electrode feeding fluid field.

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Journal of Thermal Science 2024年第1期33卷 172-189页

作者： ZHANG Zhixin ZENG Wu ZHANG Xiaodong ZENG Yuntao Advanced Gas turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas turbine Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As turbine inlet temperature gets higher and higher,thermal barrier coating(TBC) is more and more widely used in turbine *** turbine blades with TBC,it is of great significance to evaluate the temperature distribution of its substrate metal quickly and accurately,especially during the design *** different degrees of simplification such as whether to consider the change of the geometric size of the fluid domain by TBC and whether to consider the planar heat conduction in TBC,three different methods used in conjugate heat transfer(CHT) simulation to model the TBC of the turbine blades have been developed and widely used by ***,little research has been conducted to investigate the influence of the three methods on the temperature distribution of turbine *** fill this gap,three geometric models were *** are a solid conduction model with a substrate metal layer and a TBC layer,a transonic turbine vane with internal cooling and TBC,and a plate cylindrical film hole cooling model with *** methods were used in these geometric models and their differences were carefully analyzed and *** result shows that for the conduction model used in this paper,with the same TBC surface temperature distribution,the difference between the three methods is very small and can be *** a transonic turbine vane with internal cooling,regarding the local maximum temperature of the substrate-TBC interface,the largest difference between the method in which TBC is considered as a thermal resistance or a virtual layer of cells and the method in which three-dimensional heat conduction equation of TBC is solved occurs at the trailing *** difference near the leading edge is below *** employed to the film cooling model,the difference of the laterally averaged temperature of the substrate-TBC interface can be 8 K which is mainly due to the change of the length to diameter ratio of the film cooling hole by *** the substrate

关键词： turbine blade thermal barrier coating conjugate heat transfer film cooling hole

Uncertainty analysis of measured geometric variations in turbine blades and impact on aerodynamic performance

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Chinese Journal of Aeronautics 2023年第6期36卷 140-160页

作者： Xiaojing WANG Pengcheng DU Lichao YAO Zhengping ZOU Fei ZENG School of Energy and Power Engineering Beihang UniversityBejing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBejing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China

Inevitable geometric variations significantly affect the performance of turbines or even that of entire engines;thus,it is necessary to determine their actual characteristics and accurately estimate their impact on *** this study,based on 1781 measured profiles of a typical turbine blade,the statistical characteristics of the geometric variations and the uncertainty impact are analyzed,and some commonly used uncertainty modelling methods based on Principal-Component Analysis(PCA)are *** geometric variations are found to be evident,asymmetric,and non-uniform,and the non-normality of the random distributions is *** performance is notably affected,which is manifested as an overall offset,a notable scattering,and significant deterioration in several extreme ***,it is demonstrated that the PCA reconstruction model is effective in characterizing major uncertainty characteristics of the geometric variations and their impact on the performance with almost the first 10 PCA *** on a reasonable profile error and mean geometric deviation,the Gaussian assumption and stochasticprocess-based model are also found to be effective in predicting the mean values and standard deviations of the performance ***,they fail to predict the probability of some extreme cases with high ***,a Chi-square-based correction model is proposed to compensate for this *** present work can provide a useful reference for uncertainty analysis of the impact of geometric variations,and the corresponding uncertainty design of turbine blades.

关键词： Aerodynamic performance Measured geometric variations Principal-component analysis turbine blade Uncertainty analysis

Identification of crystal orientation for turbine blades with anisotropy materials

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Chinese Journal of Aeronautics 2018年第2期31卷 410-418页

作者： Yuanqiu TAN Chaoping ZANG Biao ZHOU Xiaowei WANG E.P.PETROV Jiangsu Province Key Laboratory of Aerospace Power System Nanjing University of Aeronautics and Astronautics School of Engineering of Informatics University of Sussex

A novel approach to identify the crystal orientation of turbine blades with anisotropy materials is proposed. Based on enhanced mode basis, with the main advantages of its efficiency,accuracy and general applicability, the blade vibration mode of each order is linearly constructed by several specified mode shapes, which are obtained from the considered turbine blade with specified crystal orientations correspondingly. Then, a surrogate model based on Kriging method is introduced for constructing the condensed perturbed matrix of stiffness in order to improve the efficiency even further. The constructed surrogate model allows to perform the modal analysis of turbine blades with arbitrary crystal orientations in higher efficiency, due to the fact that the elements of condensed perturbed matrix of stiffness are considered in construction of the surrogate model rather than concerning the perturbation of all the elements of the initial stiffness matrix for the blade. Genetic algorithm is finally employed to optimize the defined fitness functions in order to identify the crystal orientation angles of turbine blades. Several corresponding examples demonstrated the accuracy, efficiency and general applicability of the proposed method.

关键词： Anisotropy materials Crystal orientation Genetic algorithm Identification Surrogate model turbine blade

Design Methods and Strategies for Forward and Inverse Problems of turbine blades Based on Machine Learning

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Journal of Thermal Science 2022年第1期31卷 82-95页

作者： ZHOU Haimeng YU Kaituo LUO Qiao LUO Lei DU Wei WANG Songtao School of Energy Science and Engineering Harbin Institute ofTechnologyHarbin 150001China

To study the feasibility of using machine learning technology to solve the forward problem(prediction of aerodynamic parameters)and the inverse problem(prediction of geometric parameters)of turbine blades,this paper built a forward problem model based on backpropagation artificial neural networks(BP-ANNs)and an inverse problem model based on radial basis function artificial neural networks(RBF-ANNs).The S2(a stream surface obtained by extending a radial curve in turbo blades)calculation program was used to generate the dataset for single-stage turbo blades,and the back propagation algorithm was used to train the *** parameters of five blade sections in a single-stage turbine were selected as inputs of the forward problem model,including stagger angle,inlet geometric angle,outlet geometric angle,wedge angle of leading edge pressure side,wedge angle of leading edge suction side,wedge angle of trailing edge,rear bending angle,and leading edge *** outputs are efficiency,power,mass flow,relative exit Mach number,absolute exit Mach number,relative exit flow angle,absolute exit flow angle and reaction degree,which are eight aerodynamic *** inputs and outputs of the inverse problem model are the opposite of that of the forward problem *** models can accurately predict the aerodynamic parameters and geometric parameters,and the mean square errors(MSEs)of the forward problem test set and the inverse problem test set are 0.001 and 0.00035,*** study shows that machine learning technology based on neural networks can be flexibly applied to the design of forward and inverse problems of turbine blades,and the models built by this method have practical application value in regression prediction problems.

关键词： turbine blade forward and inverse problem machine learning neural networks parameter prediction