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Numerical Prediction and Experimental Verification of Flow Field in Hypersonic wind tunnel

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Numerical Prediction and Experimental Verification of Flow F...

作者： Xue-wen SUN Hai-bo YANG Tao MI School of Mechanical Engineering University of Science and Technology Beijing Key Laboratory of Fluid Interaction with Material Ministry of Education Centre of Excellence for Advanced Materials School of Materials Engineering North China Institute of Aerospace Engineering

The knowledge of the flow field inside the wind tunnel is an essential element for the identification of test *** the sake of obtaining more insight of the flow propagation throughout a newly built wind tunnel,numerical simulation of the flow field is performed,and the Navier–Stokes equations are solved using the computational fluid dynamics（CFD） code *** surveys of the wind tunnel flow with pressure sensors and thermocouple sensors are also performed,providing valuable data for the flow *** Mach number,temperature and pressure in the core area of the wind tunnel are obtained,and the behavior of flow propagation is quantitatively *** simulation results of the CFD model have a good agreement with the experimental *** this study,the flow field characteristics of the wind tunnel are obtained,which can provide some reference for future experiments.

关键词： Hypersonic wind tunnel Flow field Numerical simulation

A Neural Network Based Model Predictive Control for wind tunnel

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A Neural Network Based Model Predictive Control for Wind Tun...

第26届中国控制与决策会议

作者： Ning Du XiuHong Long Li Zhao High Speed Aerodynamics Institute China Aerodynamics Research and Development Center

In this study, a neural network（NN） based dynamic Mach number predictive control was proposed for a wind tunnel Match number control system. The proposed method absorbed in advantages both artificial neural network and model predictive control, for control of strong nonlinear, multiple variables, large lagging, and time-varying system. In this approach, the dynamic of wind tunnel is represented by a NN model. Then, this NN-based model was applied to the scheme of an MPC. The experimental results show that the effectiveness and set-point tracking performance of the proposed control system.

关键词： Model predictive control Neural network Multivariable wind tunnel

Decoupled PID controller for wind tunnel system

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Decoupled PID controller for wind tunnel system

第26届中国控制与决策会议

作者： Tingfeng Zhang Zhizhong Mao Ping Yuan School of Information Science and Technology Northeastern University College of Electrical Engineering Liaoning University of Technology

Implementation of a decoupled PID control strategy to a wind tunnel control system is described in this paper. Two coupled variables, stagnation pressure and Mach number, are controlled in the wind tunnel system. The wind tunnel exhibits common features of industrial systems including non-linear dynamics, time delay and coupling effects among variables. A decoupler is first introduced in this control scheme. Next, a reduced order model is determined for the decoupled wind tunnel process. Then, the PID controller is obtained using the non-dimensional tuning（NDT） algorithm. Simulation experiments have confirmed good regulatory and tracking properties of the proposed control system.

关键词： Decoupled PID control Model reduction Non-dimensional tuning wind tunnel

The Study Advances of Portable wind Erosion tunnel and Discussion about Its Several Design Conditions

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The Study Advances of Portable Wind Erosion Tunnel and Discu...

国际农业工程大会

作者： Guisheng Fan ProfessorInner Mongolia Agricultural University Zhao-Wu-Da Road No.306 HUHHOT 010018 Weiguo Dou ProfessorInner Mongolia Agricultural University Zhao-Wu-Da Road No.306 HUHHOT 010018. Hantao LiuInner Mongolia Agricultural University Zhao-Wu-Da Road No.306 HUHHOT 010018. Wenming WangInner Mongolia Agricultural University Zhao-Wu-Da Road No.306 HUHHOT 010018.

＜正＞ The paper reviewed and summarized the study advances and status of portable wind erosion tunnels, and viewed the future development tendency and application prospect. Subsequently, through the analysis and discussion about the requirements for wind erosion measurements and the requirements for simulating the near surface atmospheric boundary layer, the paper described the basic performance and functions that should be possessed for the portable wind erosion tunnels. Based on the analysis and discussion the paper finally put forward several basic aerodynamic requirements and design conditions that should be met in the design of portable wind erosion tunnels.

关键词： wind Erosion wind tunnel Design

Effects of wind speed,underlying surface,and seed morphological traits on the secondary seed dispersal in the Tengger Desert,China

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Journal of Arid Land 2024年第4期16卷 531-549页

作者： QU Wenjie ZHAO Wenzhi YANG Xinguo WANG Lei ZHANG Xue QU Jianjun Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education Ningxia UniversityYinchuan 750021China University of Chinese Academy of Sciences Beijing 100049China School of Ecology and Environment Ningxia UniversityYinchuan 750021China

The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key *** on field wind tunnel experiments using 11 common plant species on the southeastern edge of the Tengger Desert,China,we studied the secondary seed dispersal in the fixed and semi-fixed sand dunes as well as in the mobile dunes in order to understand the limitations of vegetation regeneration and the maintenance of its *** results indicated that there were significant variations among the selected 11 plant species in the threshold of wind speed(TWS).The TWS of Caragana korshinskii was the highest among the 11 plant species,whereas that of Echinops gmelinii was the *** morphological traits and underlying surface could generally explain the *** the secondary seed dispersal processes,the proportions of seeds that did not disperse(no dispersal)and only dispersed over short distance(short-distance dispersal within the wind tunnel test section)were significantly higher than those of seeds that were buried(including lost seeds)and dispersed over long distance(long-distance dispersal beyond the wind tunnel test section).Compared with other habitats,the mobile dunes were the most difficult places for secondary seed *** seeds were the easiest to be found in the semi-fixed sand dunes,whereas fixed sand dunes were the best sites for seeds that dispersed over long *** results of linear mixed models showed that after controlling the dispersal distance,smaller and rounder seeds dispersed *** index and wind speed were the two significant influencing factors on the burial of *** explanatory power of wind speed,underlying surface,and seed morphological traits on the seeds that did not disperse and dispersed over short distance was far greater than that on the seeds that were buried and dispersed over long distance,implying that the processes and mechanisms of burial and lo

关键词： seed dispersal seed morphological traits wind speed vegetation regeneration wind tunnel Tengger Desert

High-precision pose measurement method in wind tunnels based on laser-aided vision technology

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Chinese Journal of Aeronautics 2015年第4期28卷 1121-1130页

作者： Liu Wei Ma Xin Li Xiao Chen Ling Zhang Yang Li Xiaodong Shang Zhiliang Jia Zhenyuan Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education Dalian University of Technology

The measurement of position and attitude parameters for the isolated target from a highspeed aircraft is a great challenge in the field of wind tunnel simulation *** this paper,firstly, an image acquisition method for small high-speed targets with multi-dimensional movement in wind tunnel environment is proposed based on laser-aided vision *** with the trajectory simulation of the isolated model, the reasonably distributed laser stripes and selfluminous markers are utilized to capture clear images of the ***, after image processing,feature extraction, stereo correspondence and reconstruction, three-dimensional information of laser stripes and self-luminous markers are ***, a pose solution method based on projected laser stripes and self-luminous markers is ***, simulation experiments on measuring the position and attitude of high-speed rolling targets are conducted, as well as accuracy verification *** results indicate that the proposed method is feasible and efficient for measuring the pose parameters of rolling targets in wind tunnels.

关键词： High-speed motion Machine vision Pose measurement Structured light wind tunnel

Effects of Morphological Integrity of Secondary Feather on Their Drag Reduction in Pigeons

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Journal of Bionic Engineering 2022年第5期19卷 1422-1438页

作者： Qian Li Huan Shen Qingfei Han Aihong Ji Zhendong Dai Stanislav N.Gorb Institute of Bio-Inspired Structure and Surface Engineering College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing 210016China Department of Functional Morphology and Biomechanics Kiel UniversityAm Botanischen Garten 924118 KielGermany

Flight feathers of birds interact with the air flow during *** the observed low drag and high lift values at wind speeds from 9.0 to 19.8 m/s can be achieved due to the feather aerodynamics remains *** the present paper,we tested and compared morphological changes,drag reduction and flow visualization results of intact,damaged,and artificial feathers at different wind speeds in a wind *** the analysis of the drag force and resultant force angle,we proved that the integrity of feathers,whose barbs are usually closely interconnected,played an important role in the drag,which potentially triggers excellent drag reduction *** wind tunnel tests indicated that intact secondary feathers had a surprisingly high maximum drag reduction property at v?=?9 m/s compared with the feathers,where the integrity of barbs was *** hook cascades facilitated elasticity under pressure and suitable permeability in an intact feather,when the hooks were *** was indicated that the suitable permeability of intact feathers would prevent flow separation and reduce drag force at low wind speed;at high wind speed,elasticity under pressure and suitable permeability in an intact feather would facilitate strong squeezing effect,helping feathers withstand larger aerodynamic forces to which they might be subjected during *** was revealed that the intact secondary feather is a compromise between strong lift generation and drag reduction,which has a great significance for the bird’s flight.

关键词： Morphological integrity Secondary feather Drag reduction wind tunnel Smoke visualization Bioinspiration

Analysis of Bio-inspired Fishbone Based Corrugated Rib for Adaptive Camber Morphing

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Journal of Bionic Engineering 2023年第3期20卷 1083-1102页

作者： R.Jini Raj J.Bruce Ralphin Rose A.Vasudevan Department of Mechanical Engineering Anna University Regional CampusTirunelveli627007India Saveetha School of Engineering SIMATSChennai600124India

Bioinspired active camber morphing is an innovative solution for the aerodynamic performance enhancement of flight vehicles such as Micro Aerial Vehicles(MAVs)and Unmanned Aerial Vehicles(UAVs).In the present article,a bio-inspired Fish Bone Active Camber(FishBAC)corrugated rib design concept with and without a spine for an Unmanned Aerial Vehicle(UAV)is *** wing model is composed of multiple corrugated ribs and a splitted spar for connecting each *** rib geometry is subjected to static structural analysis using ANSYS Finite Element Analysis(FEA)module under the unit load *** deformation modes are first extracted from the solution of the wind tunnel test and the elastically deformed NACA 4412 profile will be used to perform Fluid-Structure Interaction(FSI)studies as a partly coupled *** corrugated rib with spine design is a stable structure as inspired from nature species that can withstand elastic and inertial *** fluid dynamics(CFD)simulation is performed to compute the coefficient of lift(Cl),coefficient of drag(Cd)at different Angle of Attack(AoA)for a modified NACA 4412 airfoil and the pressure loads acting on the deformed shape is *** Cl obtained for the modified airfoil at lower AoA is about 60–80%higher and the maximum Cl(Clmax)is 62%higher than the baseline *** Cd of modified airfoil is reduced about 20%at the AoAα=3°as compared with the baseline *** proposed corrugated rib structure has been successfully 3D printed with Polylactic Acid plus(PLA+)material and the wind tunnel testing is done to validate the Cl,Cd values obtained through CFD simulations and the results are presented.

关键词： Bioinspired design Active morphing Fish bone wind tunnel CFD

Revisiting the sex pheromone of the fall armyworm Spodoptera frugiperda,a new invasive pest in South China

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Insect Science 2022年第3期29卷 865-878页

作者： Nan-Ji Jiang Bao-Tong Mo Hao Guo Jun Yang Rui Tang Chen-Zhu Wang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing100101China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing100049China

The fall armyworm Spodoptera frugiperda is a worldwide serious agricultural pest,and recently invaded South *** pheromone can be employed to monitor its population dynamics accurately in the ***,the pheromone components previously reported by testing different geographic populations and strains are not *** the basis of confirming that the *** population from Yunnan Province belonged to the com strain,we analyzed the potential sex pheromone components in the pheromone gland extracts of females using gas chromatography coupled with electroan-tennographic detection(GC-EAD),gas chromatography coupled with mass spectrometry(GC-MS)and electroantennography(EAG).The results show that(Z)-9-tetradecenal acetate(Z9-14:Ac),(Z)-11-hexadecenyl acetate(Z11-16:Ac),(Z)-7-dodecenyl acetate(Z7-12:Ac)or(E)-7-dodecenyl acetate(E7-12:Ac)with a ratio of 100:15.8:3.9 induced EAD responses to varying degrees:Z9-14:Ac elicited a strong EAD response,Z7-12:Ac or E7-12:Ac elicited a small but clear EAD response,while Z11-16:Ac elicited a weak EAD *** single sensillum recording(SSR)showed that Z9-14:Ac and Z7-12:Ac induced dose-dependent activities in two types(A and B)of sensilla in male antennae,respectively,while the sensilla in response to E7-12:Ac and Z11-16:Ac was not ***,wind tunnel tests reveal that Z9-14:Ac and Z7-12:Ac are two principal sex pheromone components of the tested population.

关键词： GC-EAD GC-MS sex pheromone single sensillum recording wind tunnel