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脉冲等离子体激励控制翼型动态失速风洞试验研究

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气动研究与试验

气动研究与试验 2024年第2期2卷 42-51页

作者：杨鹤森梁华吴云赵光银空军工程大学等离子体动力学重点实验室陕西西安710038 西安交通大学高电压技术教研室陕西西安710049 中国空气动力研究与发展中心旋翼空气动力学重点实验室四川绵阳621000

为探索毫秒脉冲等离子体激励(AC-DBD)和纳秒脉冲等离子体激励(NS-DBD)控制翼型动态失速的效果,本文开展了SC-1095旋翼翼型的动态失速风洞试验研究。首先,基于雷诺数为6.5×105的静态翼型失速特性,设置了动态失速试验的状态。在翼型动态... 详细信息

为探索毫秒脉冲等离子体激励(AC-DBD)和纳秒脉冲等离子体激励(NS-DBD)控制翼型动态失速的效果,本文开展了SC-1095旋翼翼型的动态失速风洞试验研究。首先,基于雷诺数为6.5×105的静态翼型失速特性,设置了动态失速试验的状态。在翼型动态失速试验中,保持来流速度U_(∞)=30m/s、翼型运动规律α(t)=16°+8°sin(ωt)不变,分别在相同激励参数组合和相同功率输入条件下,对比了毫秒脉冲和纳秒脉冲等离子体气动激励控制翼型动态失速的效果。研究发现在试验设置的参数条件下,毫秒脉冲和纳秒脉冲激励均能减小翼型动态升力迟滞回线的面积,减小低头力矩并改善阻力特性;但无论是在相同的激励参数组合下还是在相同功率输入的条件下,纳秒脉冲激励的控制效果均优于毫秒脉冲激励,这体现了纳秒脉冲激励在控制翼型动态失速中的优势。

关键词：翼型动态失速等离子体脉冲激励流动控制风洞试验

Experimental study on dynamic stall control based on AC-DBD actuation

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Plasma Science and Technology 2021年第11期23卷 96-109页

作者： hesen yang Hua LIANG Guangyin ZHAO Bo WANG Shengwu ZHANG Weiliang KONG Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038People's Republic of China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000People's Republic of China National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016People's Republic of China Institute of Noise&Vibration Naval University of EngineeringWuhan 430030People's Republic of China Academician Workstation Foundation of the Green Aerotechnics Research Institute of Chonging Jiaotong University Chongqing 401120People's Republic of China

To explore AC-DBD's ability in controlling dynamic stall,a practical SC-1095 airfoil of a helicopter was selected,and systematic wind tunnel experiments were carried out through direct aerodynamic *** effectiveness of dynamic stall control under steady and unsteady actuation is *** influence of parameters such as constant actuation voltage,pulsed actuation voltage,pulsed actuation frequency and duty ratio on dynamic stall control effect is studied under the flow condition of k=0.15 above the airfoil,and the corresponding control mechanism is *** actuation can effectively reduce the hysteresis loop area of dynamic lift,and control the peak drag and moment *** unsteady actuation,there is an optimal duty ratio DC=50%,which has the best effect in improving the lift and drag characteristics,and there is a threshold of pulsed actuation voltage in dynamic stall *** optimal dimensionless frequency will not be found;different F+have different control advantages in different aerodynamic coefficients of different pitching *** actuation has obvious control advantages in improving the lift-drag characteristics and hysteresis,while steady actuation can better control the large nose-down moment.

关键词： dynamic stall plasma flow control AC-DBD parameter control law

Experimental study on surface arc plasma actuation-based hypersonic boundary layer transition flow control

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Plasma Science and Technology 2022年第9期24卷 108-116页

作者： hesen yang Hua LIANG Shanguang GUO Yanhao LUO Mengxiao TANG Chuanbiao ZHANG Yun WU Yinghong LI 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 710048People’s Republic of China

Effective control of hypersonic transition is *** order to avoid affecting the structural proflle of the aircraft,as well as reducing power consumption and electromagnetic interference,a low-frequency surface arc plasma disturbance experiment to promote hypersonic transition was carried out in theΦ0.25 m double-throat Ludwieg tube wind tunnel at Huazhong University of Science and *** printed circuit board sensors and non-contact focused laser differential interferometry testing technology were used in *** results showed that the low-frequency surface arc plasma actuation had obvious stimulation effects on the second-mode unstable wave and could promote boundary layer transition by changing the spectral characteristics of the second-mode unstable *** the same time,the plasma actuation could promote energy exchange between the second-mode unstable wave and other unstable ***,the corresponding control mechanism is discussed.

关键词： plasma actuation flow control surface arc discharge hypersonic boundary layer transition experimental study

Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

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Journal of Forestry Research 2024年第5期35卷 216-222页

作者： yang yang College of Art and Design Harbin UniversityHarbin 150076People’s Republic of China College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

As an important material for manufacturing resonant components of musical instruments,Paulownia has an important influence on the sound quality of *** this paper,a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning ***,the selection of materials for Ruan manufacturing relies primarily on manually weighing,observing,striking,and listening by the instrument *** in scientific theory have hindered the quality of the finished *** this study,nine Ruans were manufactured,and a prediction model of Ruan sound quality was proposed based on the raw material information of *** of a total of 180 data sets,145 and 45 sets were chosen for training and validation,*** this paper,typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in *** vibra-tion characteristics of the wood were tested,and a model for predicting the evaluation of Ruan’s acoustic qualities was developed by measuring the vibration characteristics of the resonating plate *** acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural *** results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard *** the model-predicted values were compared with the tradi-tional predicted results,it was found that the generalized regression neural network had good performance,achieving an accuracy of 93.8%which was highly consistent with the experimental *** was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality Wood vibration performance Paulownia wood Machine learning methods

Overview of radar detection methods for low altitude targets in marine environments

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Journal of Systems Engineering and Electronics 2024年第1期35卷 1-13页

作者： yang Yong yang Boyu School of Electronic Science National University of Defense TechnologyChangsha 410073China

In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath *** performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments.

关键词： radar sea clutter multipath scattering detection low altitude target

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： yang yang Guanxin Yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

Selective nano-buckling improves the performance of graphene logic transistors

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National Science Review 2024年第2期11卷 95-96页

作者： Tong yang Ming yang Department of Applied Physics The Hong Kong Polytechnic University Research Centre for Nanoscience and Nanotechnology The Hong Kong Polytechnic University

The massive integration of silicon-based transistors into modern electronic devices greatly increases power consumption and heat generation/dissipation[1]. In this concern, transistors based on atomically-thin graphene that exhibit high electric and thermoelectric conductivities with negligible contact resistance,

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Design Optimization and Operating Performance of S-CO_(2) Brayton Cycle under Fluctuating Ambient Temperature and Diverse Power Demand Scenarios

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Journal of Thermal Science 2024年第1期33卷 190-206页

作者： yang Jingze yang Zhen DUAN Yuanyuan Key Laboratory for Thermal Science and Power Engineering of MOE Beijing Key Laboratory for CO_(2) Utilization and Reduction TechnologyTsinghua UniversityBeijing 100084China

The supercritical CO_(2)(S-CO_(2)) Brayton cycle is expected to replace steam cycle in the application of solar power tower system due to the attractive potential to improve efficiency and reduce *** the concentrated solar power plant with thermal energy storage is usually located in drought area and used to provide a dispatchable power output,the S-CO_(2) Brayton cycle has to operate under fluctuating ambient temperature and diverse power demand *** addition,the cycle design condition will directly affect the off-design *** this work,the combined effects of design condition,and distributions of ambient temperature and power demand on the cycle operating performance are analyzed,and the off-design performance maps are proposed for the first time.A cycle design method with feedback mechanism of operating performance under varied ambient temperature and power demand is introduced *** show that the low design value of compressor inlet temperature is not conductive to efficient operation under low loads and sufficient output under high ambient *** average yearly efficiency is most affected by the average power demand,while the load cover factor is significantly influenced by the average ambient *** multi-objective optimization,the optimal solution of designed compressor inlet temperature is close to the minimum value of35℃ in Delingha with low ambient temperature,while reaches 44.15℃ in Daggett under the scenario of high ambient temperature,low average power demand,long duration and large value of peak load during the peak temperature *** the cycle designed with compressor inlet temperature of 35℃ instead of 44.15℃ in Daggett under light industry power demand,the reduction of load cover factor will reach 0.027,but the average yearly efficiency can barely be improved.

关键词： supercritical CO_(2)Brayton cycle ambient temperature fluctuating power demand scenarios design optimization off-design performance

A physics-informed deep learning framework for spacecraft pursuit-evasion task assessment

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Chinese Journal of Aeronautics 2024年第5期37卷 363-376页

作者： Fuyunxiang yang Leping yang Yanwei ZHU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Qualitative spacecraft pursuit-evasion problem which focuses on feasibility is rarely studied because of high-dimensional dynamics,intractable terminal constraints and heavy computational *** this paper,A physics-informed framework is proposed for the problem,providing an intuitive method for spacecraft threat relationship determination,situation assessment,mission feasibility analysis and orbital game rules *** the first time,situation adjustment suggestions can be provided for the weak player in orbital ***,a dimension-reduction dynamics is derived in the line-of-sight rotation coordinate system and the qualitative model is determined,reducing complexity and avoiding the difficulty of target set presentation caused by individual ***,the Backwards Reachable Set(BRS)of the target set is used for state space partition and capture zone ***-time analysis can eliminate the influence of changeable initial state and enable the proposed framework to analyze plural situations ***,a time-dependent Hamilton-Jacobi-Isaacs(HJI)Partial Differential Equation(PDE)is established to describe BRS evolution driven by dimension-reduction dynamics,based on level set ***,Physics-Informed Neural Networks(PINNs)are extended to HJI PDE final value problem,supporting orbital game rules summarization through capture zone evolution ***,numerical results demonstrate the feasibility and efficiency of the proposed framework.

关键词： Spacecraft pursuit-evasion Qualitative differential game Physics-Informed Neural Networks(PINNs) Reachability analysis Hamilton-Jacobi-Isaacs(HJI) Partial Differential Equations(PDEs)