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Experimental study of an anti-icing method over an airfoil based on pulsed dielectric barrier discharge plasma

Chinese Journal of Aeronautics 2018年第7期31卷 1449-1460页

作者： Yongqiang TIAN zhengke zhang Jinsheng CAI Leilei YANG Lei KANG National Key Laboratory of Science and Technology on Aerodynamical Design and Research Northwestern Polytechnical University

Aircraft icing has long been a plague to aviation for its serious threat to flight safety. Even though lots of methods for anti-icing have been in use or studied for quite a long time, new methods are still in great demand for both civil and military aircraft. The current study in this paper uses widely used Dielectric Barrier Discharge（DBD） plasma actuation to anti-ice on a NACA0012 airfoil model with a chord length of 53.5 cm in a closed-circuit icing wind tunnel. An actuator was installed at the leading edge of the airfoil model, and actuated by a pulsed low-temperature plasma power source. The actuator has two types of layout, a striped electrode layout and a meshy electrode *** ice accretion process or anti-icing process was recorded by a CCD camera and an infrared camera. Instantaneous pictures and infrared contours show that both types of DBD plasma actuators have the ability for anti-ice under a freestream velocity of 90 m/s, a static temperature of -7℃,an Median Volume droplet Diameter（MVD） of 20 lm, and an Liquid Water Content（LWC） of 0.5 g/m^3. The detected variations of temperatures with time at specific locations reveal that the temperatures oscillate for some time after spraying at first, and then tend to be nearly constant *** shows that the key point of the anti-icing mechanism with DBD plasma actuation is to achieve a thermal equilibrium on the model surface. Besides, the power consumption in the anti-icing process was estimated in this paper by Lissajous figures measured by an oscilloscope, and it is lower than those of existing anti-icing methods. The experimental results presented in this paper indicate that the DBD plasma anti-icing method is a promising technique in the future.

关键词： Anti,icing Icing wind tunnel Lissajous figures PlaSma actuator Pulsed dielectric barrier discharge

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Experimental Study of Rotor Flow Separation Control using a New Type of Dielectric Barrier Discharge Plasma Actuator

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Journal of Thermal Science 2019年第2期28卷 354-359页

作者： HU Xu GAO Chao HAO Jiangnan zhang zhengke XUE Ming YAN Rihua Department of Fluid Mechanics School of Aeronautics Northwestern Polytechnical University

Flow separation occurring on rotor blades is an important limiting factor for helicopter performance. This paper presents a new type of dielectric barrier discharge(DBD) plasma actuator for rotor blade flow separation control called bipolar DBD plasma actuator. The bipolar DBD plasma actuator's connection mode differs from traditional plasma actuators and eliminates reverse discharge between electrodes. The experiments in this work were carried out by smoke-wire flow visualization and PIV technology in the open test section of a low speed wind tunnel, and solved the problem of high voltage electricity supplied to the plasma actuator while the rotor rotated. In this experiment, the rotor, camera, and laser were synchronized to obtain results. Smoke-wire results and PIV results illustrated that the flow separation weakened with increasing rotor speed; the separated flow area was large at a rotating speed of 300 r/min and gradually became smaller at the rotating speed of 600 r/min, the flow separation disappeared at the rotating speed of 1200 r/min. When the plasma was active, both smoke-wire results and PIV results showed the flow separation area was greatly reduced at the rotating speed of 300 r/min and disappeared at the rotating speeds of 600 r/min and 1200 r/min, the rotor flow separation at high angles of attack could be effectively controlled by the new DBD plasma actuator.

关键词： rotor flow separation control DBD plasma PIV

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Response of ammonia-oxidizing archaea to heavy metal contamination in freshwater sediment

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Journal of Environmental Sciences 2019年第3期31卷 392-399页

作者： Ningning Li Yao Chen zhengke zhang Sha Chang Dawei Huang Sili Chen Qingwei Guo Shuguang Xie Yongxin Bing State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University South China Institute of Environmental Sciences (SCIES) Ministry of Environment Protection (MEP)

It has been well-documented that the distribution of ammonia-oxidizing bacteria(AOB) and archaea(AOA) in soils can be affected by heavy metal contamination, whereas information about the impact of heavy metal on these ammonia-oxidizing microorganisms in freshwater sediment is still lacking. The present study explored the change of sediment ammonia-oxidizing microorganisms in a freshwater reservoir after being accidentally contaminated by industrial discharge containing high levels of metals. Bacterial amoA gene was found to be below the quantitative PCR detection and was not successfully amplified by conventional PCR. The number of archaeal amoA gene in reservoir sediments were 9.62 × 10~2–1.35 × 10~7 copies per gram dry sediment. AOA abundance continuously decreased, and AOA richness, diversity and community structure also considerably varied with time. Therefore, heavy metal pollution could have a profound impact on freshwater sediment AOA community. This work could expand our knowledge of the effect of heavy metal contamination on nitrification in natural ecosystems.

关键词： Ammonia-oxidizing archaea Freshwater sediment Heavy metal Nitrosopumilus

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GRID GENERATION OF COMPLEX PRACTICAL AIRCRAFT & ZONAL SOLUTION OF EULER EQUATIONS FOR HIGH-INCIDENCE VORTICAL FLOWS(HIVF)

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Chinese Journal of Aeronautics 1997年第3期10卷 2-8页

作者： zhang zhengke, Zhu Zhiqiang, Zhuang Fenggan (Institute of Fluid Mechanics, Beijing University of Aeronautics and Astronautics, Beijing, 100083, China)

A complete process of grid generation for complex practical aircraft is described with a twin tail fighter as an example. Euler equations are discretized in the generated multiblock grid by a finite volume method and solved by a three stage explicit time stepping scheme in each block with some extra treatments of interface at each step. The predicted aerodynamic coefficients and vortical flow field are reasonable.

关键词： fighter aircraft grid generation (mathematics) elliptic partial differential equations Euler equations zonal method

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固体火箭发动机燃烧室喷管一体化网格生成

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推进技术 1999年第4期20卷 29-31页

作者：张正科刘宇北京航空航天大学宇航学院

给出固体火箭发动机燃烧室喷管一体化网格策略，用二维方法生成平面网格经旋转或堆砌形成空间网格。对网格正交性受几何域形状限制的情况进行了讨论。给出了一种燃烧室－喷管外形的网格结果。

关键词：固体火箭发动机燃烧室一体化设计格网法

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涡破裂诱导的垂尾抖振气动弹性分析

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航空学报 2016年第2期37卷 491-503页

作者：赵子杰高超张正科西北工业大学航空学院西安710072

通过试验方法分析了三角翼前缘分离涡与垂尾抖振之间的关系,深入研究了尾迹流动对垂尾抖振各阶模态的激励作用。计算得到了垂尾模型固有频率及各阶模态。在风洞试验中,应用激光片光烟流场显示技术,得到了三角翼模型在风速为30m/s下,各... 详细信息

通过试验方法分析了三角翼前缘分离涡与垂尾抖振之间的关系,深入研究了尾迹流动对垂尾抖振各阶模态的激励作用。计算得到了垂尾模型固有频率及各阶模态。在风洞试验中,应用激光片光烟流场显示技术,得到了三角翼模型在风速为30m/s下,各迎角的涡结构;使用加速度传感器测量了垂尾翼根和翼梢的抖振响应;使用热线风速仪测量了垂尾翼根和翼梢位置的脉动速度分量。结果表明:前缘涡破裂后产生的高湍流度的尾迹是垂尾抖振的直接原因,抖振边界与涡破裂的强度和位置有关;涡破裂后尾迹与垂尾产生共振,使得抖振加速度响应频率与垂尾固有频率一致;涡破裂后,在较小迎角下,尾迹对垂尾的高频振动模态的激励较为明显,在较大迎角下,涡破裂流动对垂尾低频振动模态的激励加强了。

关键词：垂尾抖振大迎角前缘涡抖振加速度振动模态

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新型人工转捩技术及风洞试验验证

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航空学报 2015年第6期36卷 1830-1838页

作者：赵子杰高超张正科西北工业大学航空学院西安710072

给出了一种新型分布型人工转捩粗糙元设计技术,该技术解决了传统人工转捩方法在跨声速风洞试验中存在的效率低、可靠性和重复性差等问题。通过理论研究确定了该转捩技术的形式,包括粗糙元形状、高度和排列方式等技术参数以及针对不同模... 详细信息

给出了一种新型分布型人工转捩粗糙元设计技术,该技术解决了传统人工转捩方法在跨声速风洞试验中存在的效率低、可靠性和重复性差等问题。通过理论研究确定了该转捩技术的形式,包括粗糙元形状、高度和排列方式等技术参数以及针对不同模型的设计方案;同时对翼型模型(NACA0012)和全机模型(GBM-01或AGARD-B标模)在不同马赫数和迎角下分别进行了测压和测力风洞试验,借助升华法,对人工转捩技术的边界层转捩效果进行了验证研究。结果表明:在不同模型上使用不同的设计方案,该转捩技术可以得到可靠的固定转捩效果,并获得具有大气飞行中高雷诺数特点的气动力结果。

关键词：跨声速空气动力学跨声速风洞人工转捩粗糙元升华法边界层

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梯度结构对氧化铝陶瓷涂层接触应力的影响

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润滑与密封 2017年第11期42卷 58-63页

作者：张政科程西云汕头大学工学院广东汕头515063

采用幂指数描述"三明治"式梯度结构形式,建立镍基氧化铝梯度陶瓷涂层在静态接触集中力载荷作用下有限元模型,分析静态接触集中力载荷作用下涂层的Mises应力分布,以及梯度层的厚度、中间层数及结构形式对涂层的Mises应力分布及最大Mises... 详细信息

采用幂指数描述"三明治"式梯度结构形式,建立镍基氧化铝梯度陶瓷涂层在静态接触集中力载荷作用下有限元模型,分析静态接触集中力载荷作用下涂层的Mises应力分布,以及梯度层的厚度、中间层数及结构形式对涂层的Mises应力分布及最大Mises应力发生位置的影响。结果表明:梯度结构对接触区Mises应力大小及分布影响不大,但影响最大Mises应力发生位置;合理的梯度结构能避开最大Mises应力发生在表面强化区及梯度区中,防止陶瓷涂层在接触载荷作用下疲劳脱落。制备层状结构梯度陶瓷涂层时,采用氧化铝层厚度20μm、线性梯度层厚度80μm、8层中间层,可改善Mises应力,适当避开最大Mises应力发生在梯度区。

关键词：梯度结构接触载荷 Mises应力氧化铝陶瓷

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