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aerodynamic design of transonic fan/compressor by 3D viscous RNS combined with genetic algorithms

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Journal of Harbin Institute of Technology(New Series) 2011年第2期18卷 143-148页

作者：姜斌王松涛冯国泰王仲奇 School of Energy Science and Engineering Harbin Institute of Technology

This paper presents an aerodynamic design of a small transonic fan by 3D viscous RNS solver combined with genetic *** aerodynamic design system based on the 3D viscous RNS solver reduces the dependency on the design experience for *** the optimum with genetic algorithms is an effective method for improving the transonic fan performance as a part of the design *** design result showed that the transonic fan designed by this method reaches the design requirement even with more efficiency value.

关键词： transonic fan aerodynamic design shock structure genetic algorithm

An aerodynamic design and numerical investigation of transonic centrifugal compressor stage

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Journal of Thermal Science 2011年第3期20卷 211-217页

作者： Weilin Yi Lucheng Ji Yong Tian Weiwei Shao Weiwei Li Yunhan Xiao School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Research Center thr Energy and Power Chinese Academy of Sciences Beijing 100190 China

In the present paper,the design of a transonic centrifugal compressor stage with the inlet relative Mach number about 1.3 and detailed flow field investigation by three-dimensional CFD are *** the CFD program was validated by an experimental *** the preliminary aerodynamic design of stage completed through in-house one-dimensional *** types of impellers and two sets of stages were computed and *** can be found that the swept shape of leading edge has prominent influence on the performance and can enlarge the flow ***,the performance of the stage with swept impeller is better than *** total pressure ratio and adiabatic efficiency of final geometry achieve 7:1 and 80% *** vane diffuser with same airfoils along span increases attack angle at higher span,and the local flow structure and performance is deteriorated.

关键词： Impeller Diffuser CFD aerodynamic design

aerodynamic design for Three-Dimensional Multi-lifting Surfaces at Transonic Flow

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Chinese Journal of Aeronautics 2006年第1期19卷 24-30页

作者：杨青真张仲寅 Thomas Streit Georg Wichmann 郑勇 School of Dynamics and Energy Northwestern Polytechnical University Xi'an 71002 China School of Aeronautics Northwestern Polytechnical University Xi'an 71002 China Institute of aerodynamics and Flow Technology German Aerospace Center(DLR) Braunschweig 38108 Germany

An aerodynamic design method and corresponding codes are developed for three-dimensional multi lifting surfaces at transonic flow. It is based on the ＂iterative residual correction＂ concept that is successfully used for transonic wing design and subsonic multi-lifting surface design. The up-wind scheme is introduced into governing equations of multi-lifting surface design method and automatically acted when supersonic flow appears on the surface. A series of interface codes are programmed, including a target-pressure modification tool. Using the improved inverse aerodynamic design code, TAU code and interface codes, the transonic multi-lifting aerodynamic design software system is founded. Two cases of canard-wing configuration have been performed to validate the method and codes. The results show that the convergence of analysis/design iteration is very good at higher speed transonic flow.

关键词： aerodynamic design transonic flow iterative residual correction multi-liftlng surfaces canard wing

aerodynamic optimization design for high pressure turbines based on the adjoint approach

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Chinese Journal of Aeronautics 2015年第3期28卷 757-769页

作者： Chen Lei Chen Jiang Heavy Engineering Research Association School of Energy and Power Engineering Beihang University

Abstract A first study on the continuous adjoint formulation for aerodynamic optimization design of high pressure turbines based on S2 surface governed by the Euler equations with source terms is presented. The objective function is defined as an integral function along the boundaries, and the adjoint equations and the boundary conditions are derived by introducing the adjoint variable vec- tors. The gradient expression of the objective function then includes only the terms related to phys- ical shape variations. The numerical solution of the adjoint equation is conducted by a finite- difference method with the Jameson spatial scheme employing the first and the third order dissipa- tive fluxes. A gradient-based aerodynamic optimization system is established by integrating the blade stagger angles, the stacking lines and the passage perturbation parameterization with the quasi-Newton method of Broyden Fletcher Goldfarb-Shanno （BFGS）. The application of the continuous adjoint method is validated through a single stage high pressure turbine optimization case. The adiabatic efficiency increases from 0.8875 to 0.8931, whilst the mass flow rate and the pressure ratio remain almost unchanged. The optimization design is shown to reduce the passage vortex loss as well as the mixing loss due to the cooling air injection.

关键词： Adjoint method aerodynamic design High pressure turbineOptimization design Objective function

aerodynamic Propeller design Using Optimization Method and Genetic Algorithm Generation

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Aerodynamic Propeller Design Using Optimization Method and G...

Conceptual design and aerodynamic Study of Joined-Wing Business Jet Aircraft

2010亚太航空航天技术研讨会

作者： Zhao Xu~* Wang Jingjing Fu Wei Han Tianshi National Key Laboratory of aerodynamic design and Research Northwestern Polytechnical University Xi’an 710072 China

＜正＞aerodynamic blade design isa critical technology influencing propeller *** paper presents a fast and convenient method for blade shape optimization and propeller performance *** on preliminary aerodynamic design results of propeller using Khodorkovsky vortex theory,single-objective and multi-objective optimization are completed using standard strip analysis and genetic algorithm with penalty function,taking propeller efficiency as objective function,blade section chord and installation angle as variables. Airfoil ARA-D with thickness from 6%～20%is *** results have been validated numerically using software FLUENT with acceptable *** model shows that single-optimized result increases propeller thrust 5%,efficiency 10.3%and decreases power 4.8%than primary desiga Two different working conditions are considered in multi-objective optimization *** results show that the integral efficiency has improved 7.6%than single-optimized ***,the optimized propeller has been simulated under other working conditions to understand its performance,for example,propeller efficiency varying with installation angle is *** the use of MATLAB as a compiler,design process is *** method and techniques presented offer a reference and guidance for aerodynamic propeller design and tends be improved for real application.

关键词： propeller aerodynamic design CFD,optimization strip analysis genetic algorithm

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Journal of Mechanics Engineering and Automation 2013年第5期3卷 263-278页

作者： Harijono Djojodihardjo Kim Em Foong Department of Aerospace Engineering Faculty of Engineering Universiti Putra Malaysia Serdang 43400 Selangor Malaysia

The concept of joined-wing aircraft with nonplanar wings as conceived and patented by Wolkovitch is attractive due to various advantages such as light weight, high stiffness, low induced drag, high trimmed CLmax, reduced wetted area and parasite drag and good stability and control, which have been supported by independent analyses, design studies and wind tunnel tests. With such foreseen advantages, the present work is carried out to design joined-wing business-jet aircraft and study and investigate its advantages and benefits as compared to the current available conventional business jet of similar size, passenger and payload capacity. In particular, the work searches for a conceptual design of joined-wing configured business-jet aircraft that possesses more superior characteristics and better aerodynamic performance in terms of increased lift and reduced drag, and lighter than the conventional business jet of similar size. Another significant objective of this work is to prove that the added rigidity possessed by the joined wing configuration can contribute to weight reduction.

关键词： Aircraft conceptual design aerodynamic design joined wing box wing.

A new non-linear vortex lattice method:Applications to wing aerodynamic optimizations

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Chinese Journal of Aeronautics 2016年第5期29卷 1178-1195页

作者： Oliviu Sugar Gabor Andreea Koreanschi Ruxandra Mihaela Botez LARCASE Laboratory of Applied Research in Active Controls Avionics and Aeroservoelasticity cole de Technologie Supérieure

This paper presents a new non-linear formulation of the classical Vortex Lattice Method （VLM） approach for calculating the aerodynamic properties of lifting surfaces. The method accounts for the effects of viscosity, and due to its low computational cost, it represents a very good tool to perform rapid and accurate wing design and optimization procedures. The mathematical model is constructed by using two-dimensional viscous analyses of the wing span-wise sections, according to strip theory, and then coupling the strip viscous forces with the forces generated by the vortex rings distributed on the wing camber surface, calculated with a fully three-dimensional vortex lifting law. The numerical results obtained with the proposed method are validated with experimental data and show good agreement in predicting both the lift and pitching moment, as well as in predicting the wing drag. The method is applied to modifying the wing of an Unmanned Aerial System to increase its aerodynamic efficiency and to calculate the drag reductions obtained by an upper surface morphing technique for an adaptable regional aircraft wing.

关键词： aerodynamic design aerodynamic optimization Enhanced potential method Morphing wing Nonlinear vortex latticemethod Quasi-3D aerodynamic method UAS optimization

aerodynamic optimization of a high-lift system with adaptive dropped hinge flap

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Chinese Journal of Aeronautics 2022年第11期35卷 191-208页

作者： Qiang JI Yufei ZHANG Haixin CHEN Junke YE School of Aerospace Engineering Tsinghua UniversityBejing 100084China 63870 PLA Troops Huayin 714200China Shanghai Aircraft design and Research Institute Shanghai 200236China

The Adaptive Dropped Hinge Flap(ADHF) is a novel trailing edge high-lift device characterized by the integration of downward deflection spoiler and simple hinge flap, with excellent aerodynamic and mechanism performance. In this paper, aerodynamic optimization design of an ADHF high-lift system is conducted considering the mechanism performance. Shape and settings of both takeoff and landing configurations are optimized and analyzed, with considering the kinematic constraints of ADHF mechanism, and the desired optimization results were obtained after optimization. Sensitivity analysis proves the robustness of the optimal design. Comparison shows that the ADHF design has better comprehensive performance of both mechanism and aerodynamics than the conventional Fowler flap and simple hinge flap design.

关键词： Adaptive dropped hinge flap aerodynamic design High-Lift aerodynamics Multidisciplinary optimization Optimization of aircraft design

Performance-Driven Multi-Objective Optimization Method for DLR Transonic Tandem Cascade Shape design

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Journal of Thermal Science 2023年第1期32卷 297-309页

作者： LI Kunhang MENG Fanjie WANG Kaibin GUO Penghua LI Jingyin School of Energy and Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

Transonic tandem cascades can effectively increase the working load,and this feature conforms with the requirement of the large loads and pressure ratios of modern axial *** paper presents an optimization strategy for a German Aerospace Center(DLR)transonic tandem cascade,with one front blade and two rear blades,at the inlet Mach number of *** tandem cascade profile was parameterized using 19 control ***-dominated sorting Genetic algorithm(NSGA-II)was used to drive the optimization evolution,with the computational fluid dynamics(CFD)-based cascade performances correction added for each *** the automatic optimization system,a pressure boundary condition iterative algorithm was developed for simulating the cascade performance with a constant supersonic inlet Mach *** optimization results of the cascade showed that the deflection of the subsonic blade changed *** shock wave intensity of the first blade row was weakened because of the reduced curvatures of the optimized pressure and suction sides of the front blade part and the downstream moved maximum thickness *** total pressure losses decreased by 15.6%,20.9%and 19.9%with a corresponding increase in cascade static pressure ratio by 1.3%,1.8%and 1.7%,for the three cascade shapes in the Pareto solution sets under the near choke,the design and near stall conditions,respectively.

关键词： transonic tandem cascade cascade parameterization strategy aerodynamic design performance-driven multi-objective optimization methodology