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Protective benefits of HDPE board sand fences in an environment with variable wind directions on Gobi surfaces:wind tunnel study
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作者 ZHANG Kai TIAN Jianjin +4 位作者 LIU Benli ZHAO Yanhua ZHANG Hailong WANG Zhenghui DENG Yuhui 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3353-3367,共15页
The Golmud-Korla Railway in the Gobi area faces operational challenges due to sand hazards,caused by strong and variable winds.This study addresses these challenges by conducting wind tunnel tests to evaluate the prot... The Golmud-Korla Railway in the Gobi area faces operational challenges due to sand hazards,caused by strong and variable winds.This study addresses these challenges by conducting wind tunnel tests to evaluate the protective benefits of High Density Polyethylene(HDPE)board sand fences,focusing on their orientation relative to various wind directions(referred to as'wind angle').This study found that the size of the low-velocity zone on the leeward side of the sand fences(LSF)expanded with an increase in the wind angle(WA).At 1H(the height of the sand fence)and 2H positions on the LSF,the wind speed profiles(WSP)exhibited a segmented logarithmic growth,constrained by Z=H at varying WAs.The efficacy of the sand fence in obstructing airflow escalated as WA increased.The size of the WA has a significant impact on the protective efficiency of HDPE board sand fences.Furthermore,compared to typical sandy surfaces,the rate of sand transport across the Gobi surface diminishes more slowly with height,attributed to the gravel's rebound effect.This phenomenon allows some sand particles to bypass the fences,rendering them less effective at blocking wind and trapping sand than in sandy environments.This paper offers scientific evidence supporting the practical use and enhancement of HDPE board sand fences in varied wind conditions. 展开更多
关键词 Variable wind directions Blown sand control wind tunnel tests HDPE board sand fences
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Design of Scale Model Mechanism in Low Speed Wind Tunnel 被引量:1
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作者 AHMAD Aldarouich 《Computer Aided Drafting,Design and Manufacturing》 2008年第2期57-64,共8页
Motion control can be considered as the synergistic collaboration of mechanical and electrical engineering, computer science and information technology to apply a controlled force to achieve useful motion in fluid or ... Motion control can be considered as the synergistic collaboration of mechanical and electrical engineering, computer science and information technology to apply a controlled force to achieve useful motion in fluid or soiled electromechanical systems. With the development of computer, electronics, and automatic control theory, motion control comes to a new stage. Great applications are based on the characteristics, stemming from advantages of electronics and modern control technology achievements, having a very good load matching property. Currently, microprocessor-based controllers are invariably used in most applications of drive electronics. The object of this work is to design a position control mechanism system, which can be used in test section of low speed wind tunnel. System load specifications and performance requirements are given. A comprehensive study of mathematical modeling of the mechanism components is given. Procedure for selection of various components with optimum parameters is discussed. After selection and calculation of system parameters to meet the performance requirements, a PID control method is adopted. 展开更多
关键词 position control servo system proportional-integral-differential control wind tunnel test MATLAB
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大跨度公铁双层斜拉桥主梁涡激共振机理与控制 被引量:1
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作者 刘志文 周威 +3 位作者 刘振标 严爱国 夏正春 陈政清 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期1-13,共13页
以拟建的某主跨808 m公铁双层斜拉桥为工程依托,采用节段模型风洞试验研究不同攻角下双层桁架梁断面的涡振性能及5种气动控制措施的抑振效果,结合计算流体动力学(CFD)静态绕流模拟,对比分析双层桁架梁断面的涡振机理及控制方法.研究表明... 以拟建的某主跨808 m公铁双层斜拉桥为工程依托,采用节段模型风洞试验研究不同攻角下双层桁架梁断面的涡振性能及5种气动控制措施的抑振效果,结合计算流体动力学(CFD)静态绕流模拟,对比分析双层桁架梁断面的涡振机理及控制方法.研究表明:主梁断面原设计方案在+3°和0°风攻角下存在明显的竖向和扭转涡振现象,且振幅超过规范允许值;间隔封闭上层桥面栏杆或增设抑流板可有效抑制主梁扭转涡振,但竖向涡振振幅仍不满足规范要求;上弦杆外侧增设风嘴可有效抑制主梁竖向和扭转涡振,而下弦杆外侧增设风嘴对主梁涡振抑振效果有限.气流经主梁原设计断面上层桥面分离后,在其上下表面形成周期性脱落的大尺度旋涡,并在上层桥面后部再附,这是主梁发生竖向涡振的主要诱因;上弦杆外侧增设风嘴可引导气流平稳通过上层桥面,消除了周期性的旋涡脱落,并在其上表面形成一段狭长“回流区”,从而有效抑制了涡振的发生. 展开更多
关键词 桥梁工程 涡激共振机理 风洞试验 双层桁架主梁 气动控制措施 计算流体动力学
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基于结构化多孔表面定常吸气的圆柱绕流场控制 被引量:1
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作者 高东来 余海洋 +1 位作者 陈文礼 李惠 《工程力学》 EI CSCD 北大核心 2024年第6期30-43,共14页
通过风洞试验研究了在雷诺数为10000时圆柱尾流主动流动控制效果,流动控制通过基于结构化多孔表面定常吸气实现,试验工况具有不同的等效吸气系数C_μ。尾流的二维流场测量通过粒子图像测速(PIV)实现,在瞬时流场结果的基础上进行本征正... 通过风洞试验研究了在雷诺数为10000时圆柱尾流主动流动控制效果,流动控制通过基于结构化多孔表面定常吸气实现,试验工况具有不同的等效吸气系数C_μ。尾流的二维流场测量通过粒子图像测速(PIV)实现,在瞬时流场结果的基础上进行本征正交分解(POD)得到模态特性、瞬时涡量演变、脉动速度功率谱、时间平均流动特性和阻力系数估计等的分析与对比,评估流动控制效果。试验结果表明:施加流动控制后的流场POD模态能量分布发生变化,旋涡的顺流向能量输运过程得到增强,当C_μ足够大时,旋涡脱落模式发生改变。剪切层沿顺流向延长,上下剪切层之间趋于平行,涡量值得到削弱。脉动速度的主频被削弱,湍流的波动和动量交换效应得到抑制;阻力系数估计值可降至无控圆柱的约11%。 展开更多
关键词 圆柱绕流 流动控制 风洞试验 粒子图像测速 多孔表面
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基于高仿生形态布局的仿鸽扑翼飞行机器人系统设计
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作者 王久斌 贺威 +2 位作者 孟亭亭 邹尧 付强 《自动化学报》 EI CAS CSCD 北大核心 2024年第2期308-319,共12页
针对现有扑翼飞行机器人存在的飞行形态与实际鸟类相差较大,以及翅膀、尾翼布局和俯仰、转向控制方式仿生度较低的问题,提出一种形态布局与鸽子相仿的扑翼飞行机器人系统设计及实现方案.通过设计弧面-折翼-后掠翅膀、仿鸟扇形尾翼以及... 针对现有扑翼飞行机器人存在的飞行形态与实际鸟类相差较大,以及翅膀、尾翼布局和俯仰、转向控制方式仿生度较低的问题,提出一种形态布局与鸽子相仿的扑翼飞行机器人系统设计及实现方案.通过设计弧面-折翼-后掠翅膀、仿鸟扇形尾翼以及尾翼挨近翅膀后缘布置的布局方式,使扑翼机器人飞行形态更加接近真实鸟类,提高扑翼机器人的形态仿生度.在此基础上,设计结合下扑角调控无需尾翼大角度上翘的俯仰控制方式,以及不依赖于尾翼的翅膀收缩转向控制方式,在提高仿生度的同时保证飞行控制的有效性.在具体设计过程中,首先参考鸽子翅膀型式选择不同类型翅膀并进行风洞测试,确定出下扑角变化时仍能保持较优升推力性能的翅膀设计方案;其次,对各种尾翼型式进行分析和比较,结合鸽子尾翼特点进行仿鸽尾翼及俯仰、转向控制机构设计,并通过风洞测试验证;最后,设计飞控系统并装配整机,进行外场飞行测试,验证仿鸽扑翼飞行机器人平台的稳定性和可控性. 展开更多
关键词 高仿生形态布局 仿鸽扑翼飞行机器人 折翼翅膀 扇形尾翼 风洞实验 俯仰控制 转向控制
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4 m×3 m风洞大迎角机构上位机软件
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作者 刘赟 黄心跃 +1 位作者 张苗苗 陈陆军 《兵工自动化》 北大核心 2024年第7期79-81,96,共4页
针对大迎角机构机械装置、控制硬件的改造升级,基于Labview框架平台设计编写上位机控制软件。优化更新基于TCP/IP协议的Socket通信,增设虚拟支杆设定、模型防碰撞识别等功能。编制的控制软件已成功应用于气动中心4 m×3 m低速风洞... 针对大迎角机构机械装置、控制硬件的改造升级,基于Labview框架平台设计编写上位机控制软件。优化更新基于TCP/IP协议的Socket通信,增设虚拟支杆设定、模型防碰撞识别等功能。编制的控制软件已成功应用于气动中心4 m×3 m低速风洞大迎角试验。结果表明,该软件有效提升了试验质量效率和设备运行安全。 展开更多
关键词 4 m×3 m低速风洞 大迎角试验 上位机控制软件
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一种连续变滚转角试验装置设计与实现
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作者 邓章林 邓晓曼 +2 位作者 马列波 王伟仲 张胜 《兵工自动化》 北大核心 2024年第6期21-26,共6页
为实现1 m量级跨超声速风洞连续变侧滑角能力,拓展试验技术范围、提升试验效率,研制一种连续变滚转角试验装置。介绍该装置的技术要求、结构设计及仿真结果,以及配套的控制系统软硬件设计,给出装置整体系统进行电磁兼容性测试、静态载... 为实现1 m量级跨超声速风洞连续变侧滑角能力,拓展试验技术范围、提升试验效率,研制一种连续变滚转角试验装置。介绍该装置的技术要求、结构设计及仿真结果,以及配套的控制系统软硬件设计,给出装置整体系统进行电磁兼容性测试、静态载荷测试及风洞试验验证结果。仿真、测试及风洞结果表明:该装置在风洞现场环境下使用具有良好的电磁兼容性,并能够有效承担风洞试验载荷要求;同时,采用连续变滚转角试验装置试验数据重复性良好、采用“常规测力中部支架+12°双转轴”支撑方式比较,试验数据规律基本一致,其小量偏差与2种方式的支撑干扰相关;该装置控制精度高、运行速度和范围均满足技术要求,可工程化应用于风洞试验。 展开更多
关键词 风洞 滚转角 电磁兼容 控制系统 试验装置
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无人机天钩回收航迹控制系统设计与实现
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作者 张剑锋 王朋飞 《火力与指挥控制》 CSCD 北大核心 2024年第2期56-62,共7页
天钩回收无人机在回收时对于航迹偏差等的控制精度要求苛刻,这对控制系统提出了挑战。提出一种用于无人机天钩回收航迹控制的新方法,设计无人机天钩回收航迹控制策略与流程,给出控制系统组成,基于某型无人机风洞试验数据,构建天钩回收... 天钩回收无人机在回收时对于航迹偏差等的控制精度要求苛刻,这对控制系统提出了挑战。提出一种用于无人机天钩回收航迹控制的新方法,设计无人机天钩回收航迹控制策略与流程,给出控制系统组成,基于某型无人机风洞试验数据,构建天钩回收无人机的线性化和非线性模型,利用优化L1航迹控制方法设计了航迹控制律,并在实际飞行试验中得到了应用,验证了所设计控制系统的正确性与工程实现性,最终的飞行试验结果表明,无人机能够在控制系统作用下实现精确天钩回收,且具有良好的动态特性。 展开更多
关键词 无人机 天钩回收 风洞试验数据 L1航迹控制
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基于自适应LMS算法的跨声速风洞模型系统辨识
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作者 李斌斌 寇西平 +4 位作者 吕彬彬 余立 杨兴华 路波 曾开春 《振动与冲击》 EI CSCD 北大核心 2024年第3期164-170,共7页
针对风洞试验模型系统辨识不准确的问题,利用自适应LMS(least mean square)滤波器模型对跨声速风洞模型进行系统辨识。由于实测信号中存在多模态耦合,为了提高系统辨识精准度,首先对输入输出信号作了FRF(frequency response analysis)... 针对风洞试验模型系统辨识不准确的问题,利用自适应LMS(least mean square)滤波器模型对跨声速风洞模型进行系统辨识。由于实测信号中存在多模态耦合,为了提高系统辨识精准度,首先对输入输出信号作了FRF(frequency response analysis)分析得到试验模型俯仰方向前两阶模态,其次利用快速Fourier变换进行模态解耦,接着利用自适应LMS滤波器模型、传递函数模型、多项式模型对俯仰方向单模态进行系统辨识,最后得到了基于自适应LMS滤波器模型的俯仰方向一阶、二阶模态滤波器系数。通过对比不同数学模型的输出与输入之间的相关系数和均方误差及辨识结果,表明自适应LMS滤波器模型具有更高的系统辨识精准度和更简洁的数学模型结构。为后续风洞试验模型振动主动控制计算法的设计提供有力支撑。 展开更多
关键词 系统辨识 自适应LMS算法 快速FOURIER变换 跨声速风洞试验 主动振动控制
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Proportional fuzzy feed-forward architecture control validation by wind tunnel tests of a morphing wing 被引量:8
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作者 Michel Joёl Tchatchueng Kammegne Ruxandra Mihaela Botez +2 位作者 Lucian Teodor Grigorie Mahmoud Mamou Youssef Mebarki 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第2期561-576,共16页
In aircraft wing design,engineers aim to provide the best possible aerodynamic performance under cruise flight conditions in terms of lift-to-drag ratio.Conventional control surfaces such as flaps,ailerons,variable wi... In aircraft wing design,engineers aim to provide the best possible aerodynamic performance under cruise flight conditions in terms of lift-to-drag ratio.Conventional control surfaces such as flaps,ailerons,variable wing sweep and spoilers are used to trim the aircraft for other flight conditions.The appearance of the morphing wing concept launched a new challenge in the area of overall wing and aircraft performance improvement during different flight segments by locally altering the flow over the aircraft's wings.This paper describes the development and application of a control system for an actuation mechanism integrated in a new morphing wing structure.The controlled actuation system includes four similar miniature electromechanical actuators disposed in two parallel actuation lines.The experimental model of the morphing wing is based on a full-scale portion of an aircraft wing,which is equipped with an aileron.The upper surface of the wing is a flexible one,being closed to the wing tip;the flexible skin is made of light composite materials.The four actuators are controlled in unison to change the flexible upper surface to improve the flow quality on the upper surface by delaying or advancing the transition point from laminar to turbulent regime.The actuators transform the torque into vertical forces.Their bases are fixed on the wing ribs and their top link arms are attached to supporting plates fixed onto the flexible skin with screws.The actuators push or pull the flexible skin using the necessary torque until the desired vertical displacement of each actuator is achieved.The four vertical displacements of the actuators,correlated with the new shape of the wing,are provided by a database obtained through a preliminary aerodynamic optimization for specific flight conditions.The control system is designed to control the positions of the actuators in real time in order to obtain and to maintain the desired shape of the wing for a specified flight condition.The feasibility and effectiveness of the developed control system by use of a proportional fuzzy feed-forward methodology are demonstrated experimentally through bench and wind tunnel tests of the morphing wing model. 展开更多
关键词 Actuators control Experimental validation Morphing wing wind tunnel test
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Gust load alleviation wind tunnel tests of a large-aspect-ratio flexible wing with piezoelectric control 被引量:5
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作者 Bi Ying Xie Changchuan +1 位作者 An Chao Yang Chao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第1期292-309,共18页
An active control technique utilizing piezoelectric actuators to alleviate gust-response loads of a large-aspect-ratio flexible wing is investigated. Piezoelectric materials have been extensively used for active vibra... An active control technique utilizing piezoelectric actuators to alleviate gust-response loads of a large-aspect-ratio flexible wing is investigated. Piezoelectric materials have been extensively used for active vibration control of engineering structures. In this paper, piezoelectric materials further attempt to suppress the vibration of the aeroelastic wing caused by gust. The motion equation of the flexible wing with piezoelectric patches is obtained by Hamilton's principle with the modal approach, and then numerical gust responses are analyzed, based on which a gust load alleviation(GLA) control system is proposed. The gust load alleviation system employs classic propor tional-integral-derivative(PID) controllers which treat piezoelectric patches as control actuators and acceleration as the feedback signal. By a numerical method, the control mechanism that piezoelectric actuators can be used to alleviate gust-response loads is also analyzed qualitatively. Furthermore, through low-speed wind tunnel tests, the effectiveness of the gust load alleviation active control technology is validated. The test results agree well with the numerical results. Test results show that at a certain frequency range, the control scheme can effectively alleviate the z and x wingtip accelerations and the root bending moment of the wing to a certain extent. The control system gives satisfying gust load alleviation efficacy with the reduction rate being generally over 20%. 展开更多
关键词 Active control Aeroelastic wing Gust load alleviation Gust response Piezoelectric actuators wind tunnel test
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Study on gust alleviation control and wind tunnel test 被引量:7
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作者 WU ZhiGang CHEN Lei YANG Chao 《Chinese Science Bulletin》 SCIE EI CAS 2013年第7期762-771,共10页
Aircraft are inevitably affected by gust during flight,which disturbs the regular operations of pilots and worsens the ride quality.In more grievous cases,flight mission cannot be completed and the flight safety may b... Aircraft are inevitably affected by gust during flight,which disturbs the regular operations of pilots and worsens the ride quality.In more grievous cases,flight mission cannot be completed and the flight safety may be disserved.In order to improve the ride quality and the fatigue life of the plane structure under the affect of gust,it is necessary to explore and validate the gust alleviation schemes.Through the low-speed wind tunnel test,the gust alleviation active control technology applied to elastic aircraft is studied.For a large-type passenger plane configuration with high aspect ratio wing,a test system was designed and three gust alleviation control schemes with PID controllers were proposed.Finally the gust alleviation control low-speed wind tunnel test was carried out in the FD-09 wind tunnel.Test results showed that at certain speed and gust frequency,all of the 3 control schemes can alleviate the acceleration at fuselage and wing-tip to a certain extent,as well as the bending moment of wing-root.The gust alleviation control scheme,which uses aileron,elevator and canard as control surfaces synthetically,gives the most satisfying gust alleviation effect. 展开更多
关键词 低速风洞试验 主动控制技术 阵风减缓 飞机结构 PID控制器 控制计划 测试系统 飞行过程
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Structural Design and Control of Variable Camber Wing Driven by Ultrasonic Motors 被引量:1
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作者 刘卫东 朱华 +2 位作者 周盛强 白亚磊 赵淳生 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第2期180-186,共7页
A novel variable camber wing driven by ultrasonic motors is proposed.Key techniques of distributed layout of drive mechanisms,coordination control of distributed ultrasonic motors as well as novel flexible skin underg... A novel variable camber wing driven by ultrasonic motors is proposed.Key techniques of distributed layout of drive mechanisms,coordination control of distributed ultrasonic motors as well as novel flexible skin undergoing one-dimensional morphing are studied.The system integration of small variable camber wing is achieved.Distributed layout of parallelogram linkages driven by geared ultrasonic motors is adopted for morphing,aimed at reducing the load for each motor and producing various aerodynamic configurations suitable for different flying states.Programmable system-on-chip(PSoC)is used to realize the coordination control of the distributed ultrasonic motors.All the morphing driving systems are assembled in the interior of the wing.The wing surface is covered with a novel smooth flexible skin in order to maintain wing shape and decrease the aerodynamic drag during morphing.Wind tunnel test shows that the variable camber wing can realize morphing under low speed flight condition.Lift and drag characteristics and aerodynamic efficiency of the wing are improved.Appropriate configurations can be selected to satisfy aerodynamic requirements of different flight conditions.The study provides a practical application of piezoelectric precision driving technology in flow control. 展开更多
关键词 variable camber wing ultrasonic motors(USMs) morphing skin control system wind tunnel test
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SEPARATION CONTROL FOR THE OUTWING OF A STRAKE-WING BY ROTATING CONE PLACED NEAR THE LEADING EDGE
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作者 Lu Zhiyong (Beijing University of Aeronautics and Astronautics, Beijing, China, 100083) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第2期79-85,共7页
Based on the research result on the strake-wing, when the size of a strakeis not large, there is a separation zone near the leading edge of the outwing of thestrake-wing at middle angles of attack. So the idea on sepa... Based on the research result on the strake-wing, when the size of a strakeis not large, there is a separation zone near the leading edge of the outwing of thestrake-wing at middle angles of attack. So the idea on separation control by rotating acone placed near the leading edge is presented. The cone surface consists of the part ofthe wing. The effect of rotating the cone on aerodynamic characteristics of thestrake-wing is investigated. The results show that a rotating surface could play an important role in controlling the flow separation for a 3-dimensional wing. For example,the relative increment in maximum lift coefficient attains 30%. The separation zone issuppressed to a certain extent. 展开更多
关键词 boundary layer control WINGS separated flow wind tunnel tests
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基于微秒脉冲激励的飞翼模型等离子体流动控制试验研究 被引量:2
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作者 牛中国 梁华 蒋甲利 《工程力学》 EI CSCD 北大核心 2023年第2期247-256,共10页
为了改善飞翼布局的大迎角气动特性,采用飞翼全模和半模分别在低速和跨声速风洞中开展了微秒脉冲介质阻挡放电等离子体流动控制的试验研究。通过流动显示和测力的试验方法研究了等离子体流动控制的主要作用机制和激励频率与激励电压等... 为了改善飞翼布局的大迎角气动特性,采用飞翼全模和半模分别在低速和跨声速风洞中开展了微秒脉冲介质阻挡放电等离子体流动控制的试验研究。通过流动显示和测力的试验方法研究了等离子体流动控制的主要作用机制和激励频率与激励电压等对飞翼模型失速特性的影响规律,验证了微秒脉冲介质阻挡放电等离子体流动控制技术从低速到亚声速的有效性,有效的试验最高马赫数Ma达到0.6、雷诺数Re达到3.05×10^(6)。试验研究表明:微秒脉冲介质阻挡放电等离子体通过非定常微尺度压缩波扰动的形式作用于翼面流场,通过频率耦合机制减弱模型的前缘分离涡、抑制翼面的流动分离;无量纲频率F^(+)是影响等离子体流动控制效果的重要参数;在低速风洞试验风速V=30 m/s时,无量纲频率F^(+)=0.35~1.06的控制效果较好,可将模型的最大升力系数提高25%以上、失速迎角推迟4°;在跨声速风洞试验马赫数Ma=0.6时,无量纲频率F^(+)=0.22和F^(+)=0.44的控制效果较好,可将模型的最大升力系数分别提高4.72%、4.77%,失速迎角分别推迟2°、1°;激励电压越高激励强度越大、等离子体流动控制效果越好。 展开更多
关键词 流体力学 流动控制 风洞试验 流动分离 等离子体 飞翼
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基于仿生尼龙丝的圆柱绕流被动控制 被引量:1
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作者 陈文礼 林隆瀚 +1 位作者 邓质 高东来 《实验流体力学》 CAS CSCD 北大核心 2023年第4期66-75,共10页
通过风洞实验研究了鸟类羽毛仿生尼龙丝对圆柱绕流场的控制效果及机理。仿生尼龙丝布置于圆柱的前驻点,雷诺数为2.67×10^(4),特征变量为尼龙丝长度与圆柱直径之比L/D。采用表面压力测量系统获取圆柱表面压力系数以分析圆柱周围的... 通过风洞实验研究了鸟类羽毛仿生尼龙丝对圆柱绕流场的控制效果及机理。仿生尼龙丝布置于圆柱的前驻点,雷诺数为2.67×10^(4),特征变量为尼龙丝长度与圆柱直径之比L/D。采用表面压力测量系统获取圆柱表面压力系数以分析圆柱周围的空气动力。利用高速粒子图像测速(PIV)系统获取圆柱的二维流场信息,并将获取的信息进行本征正交分解(POD),得到流场瞬时特性和时均特性。实验结果表明:L/D<0.6时,由尼龙丝诱导产生的旋涡无法到达尾流场,此时尼龙丝的控制效果受到限制;L/D>1.0时,尼龙丝可以显著降低圆柱尾流场的湍动能和雷诺应力,并抑制圆柱的升力系数和阻力系数;当L/D足够大时,尼龙丝可以抑制剪切层之间的相互接触,从而改变圆柱的卡门涡街旋涡脱落模式。 展开更多
关键词 圆柱尾流 空气动力 仿生 流动控制 尼龙丝 风洞实验 粒子图像测速 本征正交分解
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高马赫数内埋武器舱被动流动控制措施
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作者 张培红 陈洪杨 +3 位作者 张杰 罗磊 周方奇 贾洪印 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2023年第11期2913-2920,共8页
高马赫数(Ma>2)武器舱剪切层更强、更稳定,其噪声产生机制与通常的亚、跨、超声速武器舱流动不同,导致用来抑制空腔噪声的流动控制措施也不同。分别采用数值模拟和风洞试验2种手段,研究了圆柱形机身和马赫数对空腔流动特性的影响,以... 高马赫数(Ma>2)武器舱剪切层更强、更稳定,其噪声产生机制与通常的亚、跨、超声速武器舱流动不同,导致用来抑制空腔噪声的流动控制措施也不同。分别采用数值模拟和风洞试验2种手段,研究了圆柱形机身和马赫数对空腔流动特性的影响,以及前缘锯齿、前缘立柱、前缘横柱、前缘挡板等不同被动流动控制措施对高马赫数武器舱声压级特性的影响,为高马赫数武器舱的流动控制措施设计和研究提供参考。研究表明:圆柱形机身对空腔底部的压力分布会产生影响,压力分布的不均匀性增大,后壁附近的压力峰值增大;对通常的亚、跨、超声速武器舱流动较为有效的被动流动控制措施,对高马赫数空腔流动效果不明显,甚至会加大武器舱内的噪声等级,需要开展更为深入的研究,以设计更为有效的流动控制措施。 展开更多
关键词 武器舱 数值模拟 风洞试验 流动控制 声压级
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基于系统辨识的自适应变形机翼控制系统设计
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作者 谢长川 朱立鹏 +1 位作者 孟杨 冒森 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2023年第10期2761-2770,共10页
针对固定翼飞行器无法在复杂多变飞行环境中始终处于最优气动构型的缺陷,提出能够根据飞行环境参数自适应变形的机翼设计理念。设计了一款通过刚性翼盒偏转实现变形功能的机翼,通过面元法耦合XFOIL黏性修正器进行气动模型仿真计算,对该... 针对固定翼飞行器无法在复杂多变飞行环境中始终处于最优气动构型的缺陷,提出能够根据飞行环境参数自适应变形的机翼设计理念。设计了一款通过刚性翼盒偏转实现变形功能的机翼,通过面元法耦合XFOIL黏性修正器进行气动模型仿真计算,对该机翼的气动特性进行分析;并在此基础上设计变形机翼舵机风洞试验平台,搭建测试采集系统,对航模舵机驱动变形的气动伺服系统进行低速风洞试验,通过子空间辨识法获得了气动伺服系统的数学模型,并通过比例积分微分(PID)控制结合Smith预估控制算法的方式进行舵机补偿控制。最后根据得到的变形机翼气动数据和舵机频响特性,以优化气动性能为目标设计了一款基于舵机补偿的自适应变形机翼反馈控制系统,可以实现在复杂环境中的舵机补偿和自适应变形,对后续变形机翼的设计提供了参考。 展开更多
关键词 变形机翼设计 风洞试验 气动力计算 舵机测试 系统辨识 变形控制律
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O型套环对斜拉索涡激振动影响的试验研究 被引量:3
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作者 孙一飞 刘庆宽 +2 位作者 王仰雪 常幸 邵林媛 《工程力学》 EI CSCD 北大核心 2023年第7期239-248,共10页
斜拉索的涡激振动起振风速低,发生频繁,可能造成斜拉索的疲劳破坏,因此,斜拉索涡激振动的控制措施研究和设计十分重要。根据斜拉索涡激振动机理,提出O型套环这种气动措施来控制涡激振动,通过风洞试验,比较了标准斜拉索和套环斜拉索的涡... 斜拉索的涡激振动起振风速低,发生频繁,可能造成斜拉索的疲劳破坏,因此,斜拉索涡激振动的控制措施研究和设计十分重要。根据斜拉索涡激振动机理,提出O型套环这种气动措施来控制涡激振动,通过风洞试验,比较了标准斜拉索和套环斜拉索的涡激振动响应,研究了套环几何参数对斜拉索涡激振动的控制效果和影响规律,并初步分析了抑制振动的机理。结果表明:套环可以有效抑制斜拉索涡激振动,不同试验参数套环可将原振幅减小13%~98%;从总体趋势来说,套环宽度和厚度越大、间距越小,套环对斜拉索涡激振动的控制效果越好;安装O型套环之后,斜拉索外形表现出三维几何特征,流场的三维性被加剧,进而卡门涡的规则脱落和涡激振动被减弱。 展开更多
关键词 桥梁与隧道工程 斜拉索 风洞试验 涡激振动 振动控制 O型套环
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Virtual flight test of pitch and roll attitude control based on circulation control of tailless flying wing aircraft without rudders 被引量:4
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作者 Liu ZHANG Yong HUANG +4 位作者 Zhenglong ZHU Lihua GAO Fuzheng CHEN Fuzhang WU Meng HE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第6期52-62,共11页
Circulation Control(CC) realizes rudderless flight control by driving compressed air jet to generate a virtual rudder surface, which significantly improves low detectability. The layout plan of combined control rudder... Circulation Control(CC) realizes rudderless flight control by driving compressed air jet to generate a virtual rudder surface, which significantly improves low detectability. The layout plan of combined control rudder surface is proposed based on the tailless flying wing aircraft. The closed-loop jet actuator system and stepless rudder surface switching control strategy are used to quantitatively study the control characteristics of circulation actuator for pitch and roll attitude through 3-DOF virtual flight test in a wind tunnel with a powered model at wind speed of 40 m/s. The results show that the combined use of circulation actuators can achieve bidirectional continuous and stable control of the aircraft’s pitch and roll attitude, with the maximum pitch rate of 12.3(°)/s and the maximum roll rate of 21.5(°)/s;the response time of attitude angular rate varying with the jet pressure ratio is less than 0.02 s, which can satisfy the control response requirements of aircraft motion stability for the control system;the jet rudder surface has a strong moment control ability, and the pitch moment of the jet elevator with a pressure ratio of 1.28 is the same as that of the mechanical elevator with 28° rudder deflection, which can expand the flight control boundary. 展开更多
关键词 Active flow control Circulation control(CC) Flying wing wind tunnel test Virtual flight test
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