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Improving aircraft aerodynamic performance with bionic wing obtained by ice shape modulation

Chinese Journal of Aeronautics 2023年第2期36卷 76-86页

作者： Like XIE Hua LIANG Haohua ZONG Yun WU Yinghong LI Zhi SU Xuecheng LIU Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038China School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049China

For Unmanned Aerial Vehicles(UAVs)with limited electrical power to achieve effectively anti-/de-icing at the leading edge of the wing,a strategy of ice shape modulation was *** simulated ice shape pieces printed by 3D printing technology are mounted on a NACA0012 finite wing model,and its lift/drag coefficients and suction-side velocity fields are measured by the six-component force balance and the Particle Imaging Velocimetry(PIV),*** ratio of the spanwise length of a single ice shape piece to chord length and the spanwise length of the non-icing area between the two adjacent single ice shape pieces are defined as dimensionless ice shape length(w/c)and dimensionless modulation ratio(w/λ),*** results indicate that for a fixed w/λ,the wing lift coefficient first increases and then drops with increasing w/c,and a peak value exists when w/c is between 0.1 and *** lower the w/λis,the higher the wing lift coefficient will *** periodical variation of the flow separation area along the spanwise direction is attributed on the one hand to the acceleration effect of the flow field in the non-icing area which reduces the separation area,and on the other hand to the cross-flow caused by the streamwise vortices from the non-icing area to the icing area which promotes the mixing of the flow field(similar to vortex generators).The obtained modulation law is verified through flight tests and provides guidance for the use of ice shape modulation scheme for UAVs that cannot be completely anti-/deicing under severe weather conditions.

关键词： Dimensionless ice shape length Dimensionless modulation ratio Ice shape modulation NACA0012 finite wing Particle imaging velocimetry(PIV) Unmanned aerial vehicles(UAVs)

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Study on Detection Probability of Radar under Active and Passive Jamming

Study on Detection Probability of Radar under Active and Pas...

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2022 International Conference on Mechatronics Engineering and Artificial Intelligence, MEAI 2022

作者： Zhang, Wenyuan Xu, Haojun Chen, Zenghui Pei, Binbin Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University 710038 China

ISBN: (纸本)9781510663169

With the continuous improvement of radar performance, it is very difficult to break through the enemy's radar defense net by relying solely on trajectory planning. In actual penetration, fighters use a variety of electronic jamming methods to achieve penetration. Based on the dynamic changes of RCS, this paper model the discovery probability of penetration fighters under active jamming and passive jamming respectively, and studies the factors that affect the penetration probability and survival rate of fighters under different jamming situations. By comparing the radar detection probability with and without jamming, it is concluded that the fighter's active and passive jamming can effectively reduce the radar detection probability. This article has certain guiding significance for the fighter's dynamic penetration. © 2023 SPIE.

关键词： Jamming

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Effect of Microstructural Characteristics on Fracture Toughness in Direct Energy Deposited Novel Ti-6Al-4V-1Mo Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 119-131页

作者： Chao Xia Kexin Zhao Xin Zhou Yuqi He Panpan Gao Hengxin Zhang Guangrui Gao Fengying Zhang Hua Tan School of Material Science and Engineering Chang’an UniversityXi’an710064China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an710038China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China Surface Material Protection Co. LtdXi’an710018China

Meeting the damage tolerance requirements for engineering-grade titanium alloys pose a significant challenge in achieving high fracture toughness in direct energy deposition(DED)titanium *** work primarily investigated the relationship between the microstructure and the fracture toughness of DED new Ti-6Al-4V-1Mo *** types of microstructures were designed via two process strategies:high-line energy density(HE)and low-line energy density(LE).Relative to LE samples,HE samples possess larger-sized microstructural characteristics(coarser grain boundaryα(α_(GB)),largerαcolonies,and coarserαlaths).Lessα/βphase boundaries were formed by coarserαlaths in the HE samples,increasing the movement of dislocations,resulting in tensile strength decreasing from 1007.1 MPa(LE)to 930.8 MPa(HE)and elongation increasing from 10.8%(LE)to 15.7%(HE).Also,HE samples exhibited an excellent fracture toughness of 114.0 MPa m^(1/2),significantly higher than that of LE samples(76.8 MPa m^(1/2)).An analysis of crack propagation paths was conducted to investigate the factors contributing to *** primary factor enhancing toughness is the frequent obstruction of cracks by coarseαGB and largeαcolonies in HE ***,the pretty large-angle deflections induced by the superposition effect of coarseαGB and largeαcolonies play a vital of significant *** factors induced the long and tortuous high-energy pathways,which resulted in ultimately improved fracture *** discovered microstructural toughening mechanisms can serve as a reference for future studies involving titanium alloys,offering insights on how to enhance fracture toughness by achieving similar characteristics.

关键词： Direct energy deposition Ti-6Al-4V-1Mo Tensile properties Fracture toughness Crack propagation

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Discharge of Inductively Coupled plasma at Different Thicknesses 4th

Discharge of Inductively Coupled Plasma at Different Thickne...

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4th International Symposium on plasma and Energy Convention, ISPEC 2022

作者： Zhang, Wenyuan Xu, Haojun Wei, Xiaolong Pei, Binbin Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University Xi’an710038 China

ISBN: (纸本)9789819915750

plasma stealth technology has the characteristics of an adjustable wave absorption band, which is a new stealth technology with wider application prospects. The geometry of the cavity is an important external condition that affects the plasma discharge characteristics, while the thickness of the cavity directly determines the transmission distance of radar waves in the plasma, and a decrease in thickness will reduce the attenuation effect of the plasma on electromagnetic waves. In this paper, the effect of cavity thickness on the discharge characteristics of inductively coupled plasma (ICP) is studied, and the fluid model of inductively coupled plasma is established by the multi-physics field coupling method to obtain the distribution laws of ne and Te in ICP discharge. The heating electric field of ne is influenced by the coil structure, the peak region of ne is concentrated in the geometric center of the cavity for larger thickness, and the electron density increases with the increase of the discharge power. The results have important reference significance for the application of plasma technology in the local stealth of aircraft. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Electric power transmission

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Research Progress of hypersonic boundary layer transition control experiments

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Advances in Aerodynamics 2022年第1期4卷 341-394页

作者： He-sen Yang Hua Liang Shan-guang Guo Meng-xiao Tang Chuan-biao Zhang Yun Wu Ying-hong Li Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’anPeople’s Republic of China

Hypersonic boundary layer transition is a hot yet challenging problem restricting the development and breakthrough of hypersonic *** recent years,despite great progress made by wind tunnel experiment,transition mechanism and transition prediction,only partial knowledge has been gained so *** this paper,firstly,the specific scenarios of hypersonic boundary layer transition control are ***,the experimental research progress and mechanism of passive control and active control methods under different hypersonic transition control demands are summarized,with their advantages and disadvantages being analyzed *** actuation is easy to produce controllable broadband aerodynamic actuation,which has potential in the field of boundary layer transition ***,the following part of the paper focuses on plasma flow *** feasibility of plasma actuation to control the hypersonic boundary layer transition is demonstrated and the research ideas are ***,hypersonic boundary layer transition control methods are summarized and the direction of future research is prospected.

关键词： Hypersonic boundary layer Transition control Active/passive control Experimental research plasma actuation

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Experimental investigation on de-icing by an array of impact rod-type plasma synthetic jets

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plasma science and technology 2023年第3期25卷 138-149页

作者：刘雪城梁华宗豪华谢理科苏志 Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038People’s Republic of China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China

Since flight accidents due to aircraft icing occur from time to time,this paper proposes an array of impact rod-type plasma synthetic jet de-icing methods for aircraft icing *** impact rod-type plasma synthetic jet actuator(PSJA)is based on the traditional PSJA with an additional impact rod structure for better de-icing in the flight *** this work,we first optimize the ice-breaking performance of a single-impact rod-type PSJA,and then conduct an array of impact rod-type plasma synthetic jet ice-breaking experiments to investigate the relationship between crack expansion and discharge energy,ice thickness and group *** results show that the impact force and impulse of a single-impact rod-type PSJA are proportional to the discharge energy,and there exists a threshold energy Qmin for a single actuator to break the ice,which is proportional to the ice *** when the discharge energy reaches above Qmin can the ice layer produce cracks,and at the same time,the maximum radial crack length produced during the ice-breaking process is proportional to the discharge *** the ice is broken by an array of impact rod PSJAs,the discharge energy and group spacing together determine whether the crack can be extended to the middle region of the *** the group spacing is certain,increasing the energy can increase the intersection of cracks in the middle region,and the ice-fragmentation degree is increased and the ice-breaking effect is *** the same time,the energy estimation method of ice breaking by an array of impact rod-type PSJAs is proposed according to the law when a single actuator is breaking ice.

关键词： plasma de-icing plasma synthesis jet force measurement high-speed photography ice cracks

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Investigation of the interaction between NS-DBD plasma-induced vortexes and separated flow over a swept wing

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plasma science and technology 2023年第1期25卷 88-99页

作者：刘备梁华郑博睿 Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038People's Republic of China The Green Aerotechnics Research Institute of Chongqing Jiaotong University Chongqing 401120People's Republic of China

The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and separated *** order to study the mechanism of NS-DBD plasma flow separation control over a swept wing,especially the influence of the actuation frequency,at first,experimental studies of the actuation frequencies at 100 Hz are conducted to validate the numerical simulation ***,numerical studies of different actuation frequencies which are 50 Hz,100 Hz,160 Hz,200 Hz,500 Hz,and 1000 Hz,respectively are *** interaction between the plasma-induced vortexes and the separated flow is *** show that there is a range of the actuation frequency which includes the frequency(160 Hz) calculated by the average aerodynamic chord length to make the control effect good,but when the actuation frequencies are too low(50 Hz) or too high(1000 Hz),the control effect will get *** former is because plasmainduced vortexes disappear in a period within an actuation cycle;the latter is because plasma-induced vortexes cannot develop completely,resulting in a weak vortex intensity.

关键词： plasma-induced vortex flow separation control NS-DBD LES

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Machine learning for predicting fatigue properties of additively manufactured materials

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Chinese Journal of Aeronautics 2024年第4期37卷 1-22页

作者： Min YI Ming XUE Peihong CONG Yang SONG Haiyang ZHANG Lingfeng WANG Liucheng ZHOU Yinghong LI Wanlin GUO State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Institute for Frontier Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Shenyang Engine Research Institute Shenyang 110015China Liaoning Key Laboratory of Impact Dynamics on Aero Engine Shenyang 110015China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038China

Fatigue properties of materials by Additive Manufacturing(AM) depend on many factors such as AM processing parameter, microstructure, residual stress, surface roughness, porosities, post-treatments, etc. Their evaluation inevitably requires these factors combined as many as possible, thus resulting in low efficiency and high cost. In recent years, their assessment by leveraging the power of Machine Learning(ML) has gained increasing attentions. A comprehensive overview on the state-of-the-art progress of applying ML strategies to predict fatigue properties of AM materials, as well as their dependence on AM processing and post-processing parameters such as laser power, scanning speed, layer height, hatch distance, built direction, post-heat temperature,etc., were presented. A few attempts in employing Feedforward Neural Network(FNN), Convolutional Neural Network(CNN), Adaptive Network-Based Fuzzy Inference System(ANFIS), Support Vector Machine(SVM) and Random Forest(RF) to predict fatigue life and RF to predict fatigue crack growth rate are summarized. The ML models for predicting AM materials' fatigue properties are found intrinsically similar to the commonly used ones, but are modified to involve AM features. Finally, an outlook for challenges(i.e., small dataset, multifarious features,overfitting, low interpretability, and unable extension from AM material data to structure life) and potential solutions for the ML prediction of AM materials' fatigue properties is provided.

关键词： Additive manufacturing Machine learning Fatigue life Fatigue crack growth rate Prediction

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Modulating sparks in a pulse train for repetitive and energy efficient plasma generation

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High Voltage 2023年第6期8卷 1168-1179页

作者： Bo Yin Yifei Zhu Yun Wu Institute of Aero‐Engine School of Mechanical EngineeringXi'an Jiaotong UniversityXi'anChina School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina Science and Technology of Plasma Dynamics Laboratory Airforce Engineering UniversityXi'anChina

Spark is a widely studied plasma source for active species production;however,it ex-periences unstable transitions(*** a thermal arc)at high frequencies or long pulse *** this study,the sparks generated in a pulse train were studied and modulated based on a physics‐corrected deep learning *** results show that a highly repeatable and stable spark plasma source can be achieved by automatically adjusting the voltage amplitude according to the discharge frequency in a high‐frequency pulse train within the time scale of the fluid *** influences of the electron number density increasing mode and modulated driven voltage profiles on the energy efficiencies were also studied.

关键词： Spark pulse energy

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Turbulent drag reduction by sector-shaped counter-flow dielectric barrier discharge plasma actuator

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Chinese Physics B 2025年第2期34卷 362-370页

作者： Borui Zheng Shaojie Qi Minghao Yu Jianbo Zhang Linwu Wang Dongliang Bian School of Automation and Information Engineering Xi’an University of TechnologyXi’an 710048China School of Mechanical and Precision Instrument Engineering Xi’an University of TechnologyXi’an 710048China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038China Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi’an 710048China Shaanxi University Key Laboratory of Photonic Power Devices and Discharge Regulation Xi’an 710048China

The primary objective in aircraft transportation is to minimize turbulent drag, thereby conserving energy and reducing emissions. We propose a sector-shaped counter-flow dielectric barrier discharge plasma actuator, which leverages jet synthesis for drag reduction. A drag control experiment was conducted in a low-speed wind tunnel with a controlled flow velocity of 9.6 m/s(Re = 1.445 × 10^(4)). This study investigated the effects of varying pulse frequencies and actuation voltages on the turbulent boundary layer. Using a hot-wire measurement system, we analyzed the pulsating and time-averaged velocity distributions within the boundary layer to evaluate the streamwise turbulent drag reduction. The results show that the local TDR decreases as the pulse frequency increases, reaching a maximum reduction of approximately 20.97% at a pulse frequency of 50 Hz. In addition, as the actuation voltage increases, the friction coefficient decreases, increasing the drag reduction rate. The maximum drag reduction of approximately 33.34% is achieved at an actuation voltage of 10 kV.

关键词： plasma flow control turbulent boundary layer turbulent drag reduction

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