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An experimental investigation on static directiona stability

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Chinese Journal of Aeronautics 2016年第6期29卷 1527-1540页

作者： Wen Jing wang yankui Deng Xueying School of Aeronautic Science and Engineering Beihang University

A generic aircraft usually loses its static directional stability at moderate angle of attack(typically 20–30°). In this research, wind tunnel studies were performed using an aircraft model with moderate swept wing and a conventional vertical tail. The purpose of this study was to investigate flow mechanisms responsible for static directional stability. Measurements of force, surface pressure and spatial flow field were carried out for angles of attack from 0° to 46° and sideslip angles from-8° to 8°. Results of the wind tunnel experiments show that the vertical tail is the main contributor to static directional stability, while the fuselage is the main contributor to static directional instability of the model. In the sideslip attitude for moderate angles of attack, the fuselage vortex and the wing vortex merged together and changed asymmetrically as angle of attack increased on the windward side and leeward side of the vertical tail. The separated asymmetrical vortex flow around the vertical tail is the main reason for reduction in the static directional stability. Compared with the wing vortices, the fuselage vortices are more concentrated and closer to the vertical tail, so the yawing moment of vertical tail is more unstable than that when the wings are absent. On the other hand,the attached asymmetrical flow over the fuselage in sideslip leads to the static directional instability of the fuselage being exacerbated. It is mainly due to the predominant model contour blockage effect on the windward side flow over the model in sideslip, which is strongly affected by angle of attack.

关键词： Asymmetric flow Directional stability Flow mechanisms Sideslip Yawing moment

Influence of artificial tip perturbation on asymmetric vortices flow over a chined fuselage

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Chinese Journal of Aeronautics 2015年第4期28卷 1016-1022页

作者： Shi Wei Deng Xueying Tian Wei wang yankui Ministry-of-Education Key Laboratory of Fluid Mechanics Beihang University

An experimental study was conducted with the aim of understanding behavior of asymmetric vortices flow over a chined *** tests were carried out in a wind tunnel at Reynolds number of 1.87 · 105 under the conditions of high angles of attack and zero angle of *** results show that leeward vortices flow becomes asymmetric vortices flow when angle of attack increases over *** asymmetric vortices flow is asymmetry of two forebody vortices owing to the increase of angle of attack but not asymmetry of vortex breakdown which appears when angle of attack is above *** vortices flow is sensitive to tip perturbation and is nondeterministic due to randomly distributed natural minute geometrical irregularities on the nose tip within machining *** asymmetric vortices flow can be obtained by attaching artificial tip perturbation which can trigger asymmetric vortices flow and decide asymmetric vortices flow *** by artificial tip perturbation, the vortex on the same side with perturbation is in a higher position, and the other vortex on the opposite side is in a lower *** suction on the lower vortex side is larger, which corresponds to a side force pointing to the lower vortex side.

关键词： Asymmetric vortices flowChined fuselage Tip perturbation High angle of attack Flow regimes

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碳化硼陶瓷的高温高压制备及性能研究

超硬材料工程 2024年第1期36卷 35-40页

作者：王方标魏瑞莹王丽娟王艳奎牡丹江师范学院黑龙江省省级重点超硬材料实验室黑龙江牡丹江157011

利用六面顶液压机,以铝、钴为烧结助剂,在压力5.0-5.5 GPa、温度1 350-1 700℃、保温时间5 min的条件下制备出碳化硼陶瓷,并通过XRD衍射仪、SEM扫描电镜、维式硬度仪对其进行了物相分析、微观形貌表征和硬度测量,研究了压力、温度对碳... 详细信息

利用六面顶液压机,以铝、钴为烧结助剂,在压力5.0-5.5 GPa、温度1 350-1 700℃、保温时间5 min的条件下制备出碳化硼陶瓷,并通过XRD衍射仪、SEM扫描电镜、维式硬度仪对其进行了物相分析、微观形貌表征和硬度测量,研究了压力、温度对碳化硼复合陶瓷力学性能的影响。实验结果表明,在5.5 GPa、1 550℃时,碳化硼陶瓷具有较好的综合性能,维式硬度为4 022 HV、磨耗比为2.5。其中铝、钴作为烧结助剂不仅降低了烧结温度还促进烧结反应,增强颗粒间的扩散促使陶瓷更快地达到高致密度,改善其力学性能。

关键词：高温高压碳化硼硬度磨耗比

Fe_(2)O_(3)/Al_(2)O_(3)修饰的混合金属氧化物降解维C生化废水

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应用化工 2024年第6期53卷 1347-1351页

作者：韩永辉王艳魁刘姿伶岳琳何淑妍邱珊河北科技大学环境科学与工程学院河北石家庄050018 河北碧蓝环保工程有限公司河北石家庄050041 哈尔滨工业大学市政环境工程学院黑龙江哈尔滨150006

针对维C废水在二级生化处理后很难达到排放标准的问题,以铁铝混合粉末作为载体(Fe_(2)O_(3)/Al_(2)O_(3),FA)与其他金属氧化物粉末混合掺杂,通过滚动造粒法制备混合金属氧化物(MMO)臭氧催化剂,用于降解维C生化废水。结果表明,CuO、Ni_(2... 详细信息

针对维C废水在二级生化处理后很难达到排放标准的问题,以铁铝混合粉末作为载体(Fe_(2)O_(3)/Al_(2)O_(3),FA)与其他金属氧化物粉末混合掺杂,通过滚动造粒法制备混合金属氧化物(MMO)臭氧催化剂,用于降解维C生化废水。结果表明,CuO、Ni_(2)O_(3)协同催化,所制备的MMO臭氧催化剂Cu-Ni/FA具有较好的催化性能和力学性能。通过SEM、TEM、BET、XRD、XPS对样品的理化性能进行表征,发现催化体系中NiFe_(2)O_(3)和Cu_(4)O_(3)发挥了重要作用。在废水COD浓度为248.31 mg/L,pH为7,催化剂投加量35 g/L以及臭氧浓度10 mg/L条件下,60 min时COD去除效率达到70%。超声120 min后催化剂脱落率为2.724%,对每次超声后的催化剂进行催化臭氧氧化实验,COD去除率为65%~69%,表明该催化剂具有良好的抗脱落性和稳定性。

关键词：金属氧化物混合掺杂臭氧催化氧化维C生化废水

Mechanism of perturbation-combined active control technique for asymmetric vortex flow over slender body at high angle of attack

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Science China(Technological Sciences) 2011年第10期54卷 2665-2673页

作者： wang yankui SHAN JiXiang TIAN Wei DENG XueYing DONG JinGang TIAN Xiao Key Laboratory of Fluid Mechanics (Beihang University) Ministry of Education BUAA Beijing 100191 China

Based on the determinability of asymmetric vortices flow over slender body under changeless round grain at high angle of attack,the effect of microblowing set in special position on the behaviors of asymmetric flow is discussed in this paper,including blowing momentum and circumferential locations of the microblowing hole of 0.5 mm in diameter on nose tip.A new kind of active control technique,named perturbation-combined active control technique,which combines the micro-grain and micro-blowing perturbation,was proposed on the basis of the *** control technique can not only change the sign of side force of slender body arbitrarily through changing the vortices positions between yaw-left and yaw-right configuration,but also can make the magnitude of side force variable gradually even at bistable state of asymmetric ***,the interferential mechanism of the perturbation-combined active control technique has also been concluded from this *** tests have been conducted at low speed wind tunnel with subcritical Reynolds number of 1.05×10~5 at angle of attack α=50° in Beihang University,Beijing,China.

关键词： asymmetric vortex perturbation-combined active flow control high angle of attack aerodynamics slender body

Nose micro-blowing for asymmetric vortices control on blunt-nose slender body at high angle of attack

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Theoretical & Applied Mechanics Letters 2017年第6期7卷 351-356页

作者： Lei wang yankui wang Zhongyang Qi Ministry-of-Education Key Laboratory of Fluid Mechanics Beihang UniversityBeijing 100191China

The asymmetric vortices over blunt-nose slender body at high angles of attack result in random side force. In this paper, a nose micro-blowing technology is used to control the asymmetric flow. Pressure measurement and particle image velocimetry （PIV） experiments are conducted in a low-speed wind tunnel to research effects of jet flow rate on asymmetric vortices over blunt-nose slender body. The angle of attack of the model is fixed at 50° and the Reynolds number for the experiments is 1.6× 105 based on diameter of aftbody. A blow hole （5 mm in diameter） on the nose is processed at circumferential angle θb = 90° and meridian angleγb = 20° with jet momentum ratio Cμ ranging from 5.30× 10-7 to 1.19 × 10-4. Tests are made under two kinds of perturbations. One is called single perturbation with only blow hole and the other is called combined perturbation consists of blow hole and additional granules set on nose. The results show that whether the model has the single perturbation or the combined one, the sectional side force ofx/D = 3 varies in the same direction with the increasement of Cμ and remains stable when Cμ is greater than 3.29× 10- 6. But the stable force values are different according to various perturbations. The fact proves that the size and direction of the side force of blunt-nose slender body can be controlled by the nose micro-blowing.

关键词： Nose micro-blowinglAsymmetric vorticeslBlunt-nose slender bodylHigh angle of attacklFlight control

Study on flow behavior and structure over chined fuselage at high angle of attack

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Science China(Technological Sciences) 2010年第8期53卷 2057-2067页

作者： TIAN Wei,DENG XueYing ,wang yankui,FAN GuoLei&DONG Chao Ministry of Education Key Laboratory of Fluid Mechanics,Beijing University of Aeronautics and Astronautics,Beijing 100191,China 1. Ministry of Education Key Laboratory of Fluid Mechanics Beijing University of Aeronautics and Astronautics Beijing 100191 China

A study of leeward vortex structure over chined fuselage and the effects of micro tip perturbation on its vortex flow have been carried out in wind tunnel experiments at Reynolds numbers from 1.26×105 to 5.04×105 with PIV and pressure measurement ***,the experiment results have proved that micro tip perturbation has no effects on the vortex flow and its aerodynamic characteristics over chined fuselage at high angle of attack,in which there are not any non-deterministic flow ***,the evolution of leeward vortex structure over chined fuselage along the axis of model can be divided into four flow regimes:linear conical developed regime,decay regime of leeward vortex intensity,asymmetric leeward vortex break down regime and completely break down *** a correlation between leeward vortex structure and sectional aerodynamic force was also revealed in the present ***,the experiment results show the behavior of leeward vortex core trajectories and zonal characteristics of leeward vortex structure with angles of ***,the experiment results of Reynolds number effect on the leeward vortex flow have further confirmed research conclusions from previous studies:the flows over chined fuselage at high angles of attack are insensitive to variation of Reynolds number,and there is a little effect on the secondary boundary layer separation and the suction peak induced by leeward vortex.

关键词： high angle of attack aerodynamics chined fuselage tip perturbation leeward vortex structure zonal characteristics

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钝头旋成体背涡迎角效应的分区性态

北京航空航天大学学报 2018年第10期44卷 2134-2140页

作者：齐中阳王延奎曹鹏空气动力学国家重点实验室绵阳621000 北京航空航天大学航空科学与工程学院北京100083 上海航天控制技术研究所上海200233

为了实现空空导弹的高机动性,基于模型后体直径D以及试验风速的雷诺数Re_D=1.54×10~5,通过风洞测力和测压试验对钝头旋成体背涡流动特性随迎角的演化形式进行了研究。根据对模型不同迎角下所受侧向力、截面压力分布以及截面侧向力系数... 详细信息

为了实现空空导弹的高机动性,基于模型后体直径D以及试验风速的雷诺数Re_D=1.54×10~5,通过风洞测力和测压试验对钝头旋成体背涡流动特性随迎角的演化形式进行了研究。根据对模型不同迎角下所受侧向力、截面压力分布以及截面侧向力系数随时间波动情况的分析,确定了不同迎角下的钝头旋成体背涡流动形式。以此划分了4个迎角分区:附着流动区(α≤10°)、对称涡流动区(10°50°)。对各迎角分区的背涡流动特性进行了详细讨论。

关键词：钝头旋成体背涡结构迎角效应非对称流动大迎角空气动力学

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前体非对称涡高风速烟雾显示技术

力学学报 2007年第2期39卷 261-266页

作者：柏楠邓学蓥王延奎北京航空航天大学流体力学教育部重点实验室北京100083

通过在细长旋成体模型机身的不同位置设置出烟孔,使用新型发烟装置对模型注入雾化油滴,采用激光片光法在常规风洞中高风速(60m／s)条件下得到清晰、完整而稳定的截面涡结构图像．并通过同状态标定法和等比例网格法发展了简易涡位定量测... 详细信息

通过在细长旋成体模型机身的不同位置设置出烟孔,使用新型发烟装置对模型注入雾化油滴,采用激光片光法在常规风洞中高风速(60m／s)条件下得到清晰、完整而稳定的截面涡结构图像．并通过同状态标定法和等比例网格法发展了简易涡位定量测量技术,为前体非对称涡Re数效应的研究提供了重要的技术平台．

关键词：高风速流场显示定量测量 Re数效应前体非对称涡大迎角