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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

Index allocation for a reusable LOX/CH4 rocket engine

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Chinese Journal of Aeronautics 2021年第2期34卷 432-440页

作者： Yi LI Jie FANG Bing SUN Kaiyang LI Guobiao CAI School of Astronautics Beihang UniversityBeijing 100083China Key Laboratory of Spacecraft Design optimization and Dynamic Simulation Technologies(Beihang University) Ministry of EducationBeijing 100083China

Reusable rocket engines are the core components of reusable launch vehicles, and have thus become a major focus of aerospace engineering research in recent years. In practice, subsystem design is based on the overall index allocation of an engine;therefore, a multidisciplinary optimization approach is necessary. In this study, design of a reusable methane/liquid oxygen(LOX/CH4)rocket engine with a gas generator cycle was investigated using multidisciplinary optimization. Two parameters were chosen as design variables: pressure and fuel mix ratio of the main combustion chamber. optimization objectives were specific impulse, structural mass, and life cycle cost of the reusable rocket engine, and constraints were assigned to each discipline according to rocket design requirements. Then, an optimization model was developed, and optimal design parameters were acquired for the LOX/CH4 rocket engine. The proposed method is effective for designing the index allocation of reusable rocket engines and takes into account the multidisciplinary nature of complex systems.

关键词： Index allocation Mass model multidisciplinary optimization Reliability Rocket engines

An improved multidisciplinary feasible method using DACE approximation approach

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Journal of Systems Engineering and Electronics 2005年第2期16卷 335-340页

作者： SuZijian XiaoRenbin ZhongYifang CADCenter SchoolofMechanicalEngineeringandScienceHuazhongUniversityofScience&TechnologyWuhan430074P.R.China

multidisciplinary feasible method (MDF) is conventional method to multidisciplinary optimization (MDO) and well-understood by users. It reduces the dimensions of the multidisciplinary optimization problem by using the design variables as independent optimization variables. However, at each iteration of the conventional optimization procedure, multidisciplinary analysis (MDA) is numerously performed that results in extreme expense and low optimization efficiency. The intrinsic weakness of MDF is due to the times that it loop fixed-point iterations in MDA, which drive us to improve MDF by building inexpensive approximations as surrogates for expensive MDA. An simple example is presented to demonstrate the usefulness of the improved MDF. Results show that a significant reduction in the number of multidisciplinary analysis required for optimization is obtained as compared with original MDF and the efficiency of optimization is increased.

关键词： multidisciplinary optimization approximation multidisciplinary feasible method (MDF).

Genetic algorithms in bidisciplinary (aerodynamics/electro-magnetism) optimization

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Science China Technological Sciences 2001年第6期44卷 572-580页

作者：朱自强李海明李津于日新 Beijing Univ. Aero. and Astronaut. Beijing 100083 China

The genetic algorithm(GA) is a non-traditional, probability search and global optimization method similar to natural selection and evolution. The key points and control parameters of this method are briefly discussed. To apply it to a multiobjective and multidisciplinary optimization problem a kind of fitness function is suggested, in which the requirements of multiobjects and multiconstraints are considered and the nondimensional coefficients and panalty coefficients of the constraint function are also introduced . Numerical results of bidisciplinary optimization calculation show that the present method is effective, applicable, and robust.

关键词： genetic algorithm multidisciplinary optimization deterministic optimization.