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Numerical aerodynamic analysis of bluff bodies at a high Reynolds number with three-dimensional CFD modeling

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Science China(Physics,Mechanics & Astronomy) 2013年第2期56卷 277-289页

作者： BAI YuGuang YANG Kai SUN DongKe ZHANG YuGuang KENNEDY David WILLIAMS Fred GAO XiaoWei State Key Laboratory of Structural analysis for Industrial Equipment Faculty of Vehicle Engineering and MechanicsDalian University of Technology Cardiff School of Engineering Cardiff UniversityCardiff CF24 3AAWalesUK

This paper focuses on numerical simulations of bluff body aerodynamics with three-dimensional CFD(computational fluid dynamics) modeling,where a computational scheme for fluid-structure interactions is *** choice of an appropriate turbulence model for the computational modeling of bluff body aerodynamics using both two-dimensional and three-dimensional CFD numerical simulations is also *** efficient mesh control method which employs the mesh deformation technique is proposed to achieve better simulation *** long-span deck sections are chosen as examples which were stationary and pitching at a high Reynolds *** the proposed CFD method and turbulence models,the force coefficients and flutter derivatives thus obtained are compared with the experimental measurement results and computed values completely from commercial ***,a discussion on the effects of oscillation amplitude on the flutter instability of a bluff body is carried out with extended numerical *** numerical analysis results demonstrate that the proposed three-dimensional CFD method,with proper turbulence modeling,has good accuracy and significant benefits for aerodynamic analysis and computational FSI studies of bluff bodies.

关键词： bluff body aerodynamic analysis fluid-structure interaction three-dimensional CFD modeling flutter

aerodynamic analysis OF HELICOPTER SHROUDED TAIL ROTOR BY MOMENTUM THEORY

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Transactions of Nanjing University of Aeronautics and Astronautics 1998年第2期15卷 50-54页

作者：徐国华王适存南京航空航天大学直升机技术研究所

In this paper, in order to clarify the gains of the shroud in the shrouded tail rotor system, a thrust division factor q , which represents the ratio of the shroud thrust to the total thrust of the shrouded tail rotor, is introduced. With the help of q , the slipstream theory for the static and axial flow states of the shrouded tail rotor are fully derived. Based on the sliptream theory, the variations of the thrust, power and disk area against q for different cases are emphatically analysed and the comparisons between a shrouded tail rotor and an isolated one are made. It is shown that, although the shroud can provide as much as 50% of the total thrust of shrouded tail rotor for the static state, the thrust gains of the shroud rapidly decrease for the axial flow state, which depends on the flow velocity ratio.

关键词： helicopters tail rotors shroud aerodynamic analysis

Robust design and analysis of a conformal expansion nozzle with inverse-design idea

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Chinese Journal of Aeronautics 2018年第1期31卷 79-88页

作者： Wenbiao GAN Xiaocui ZHANG Tielin MA Qinling ZHANG Wu YUAN Research Institute of Unmanned System Beihang University The First Aircraft Institute Aviation Industry Corporation of China Computer Network Information Center Chinese Academy of Sciences

This paper examines robust optimization design and analysis of a conformal expansion nozzle of flying wing Unmanned Aerial Vehicle （UAV） with the inverse-design idea. In view of flow features and stealth constraints, the inverse-design idea is described and the uncertainty-based robust design model is presented. A robust design system employs this model to combine deterministic optimization and robust optimization and is applied into design of a conformal expansion nozzle. The results indicate that design optimization can conform to the anticipation of the inversedesign idea and significantly improve the aerodynamic performance that meet the requirement of 6σ. The present method is a feasible nozzle design strategy that integrates robust optimization and inverse-design.

关键词： aerodynamic analysis Inverse-design Nozzle Off-design Robust optimization