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Unsteady aerodynamic noise prediction of contra-rotating open rotor using meshless method

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Chinese Journal of Aeronautics 2024年第8期37卷 144-165页

作者： Zhiliang HONG Meng SU Haitao ZHANG Zerui XU Lin DU Lingfeng CHEN College of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China Civil aviation Administration of China Beijing 100710China research institute of Aero-Engine Beihang UniversityBeijing 100191China

The Contra-Rotating Open Rotor(CROR)design confronts significant noise challenges despite being one of the possible options for future green *** efficiently estimate the noise emitted from a CROR,a three-dimensional unsteady prediction model based on the meshless method is *** unsteady wake flow and the aerodynamic load fluctuations on the blade are solved through the viscous vortex particle method,the blade element momentum theory and vortex lattice ***,the acoustic field is obtained through the Farassat’s formulation *** of this method is conducted on a CROR,and a mesh-based method,e.g.,Nonlinear Harmonic(NLH)method,is also employed for *** is found that the presented method is three times faster than NLH method while maintaining a comparable precision.A thorough parametric analysis is also carried out to illustrate the effects of rotational speed,rotor-rotor spacing and rear rotor diameter on the noise *** rotor speed is found to be the most influencing factor,and by optimizing the speed difference between the front and rear rotors,a notable noise reduction can be *** current findings not only contribute to a deeper comprehension of the CROR’s aeroacoustic properties but also offer an effective tool for engineering applications.

关键词： Contra-Rotating Open Rotor(CROR) Aerodynamic noise Blade element momentum theory Viscosity vortex particle method Farassat’s formulation 1A

Constructal design of printed circuit recuperator for S-CO_(2)cycle via multi-objective optimization algorithm

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Science China(Technological Sciences) 2024年第1期67卷 285-294页

作者： DAN ZhiSong FENG HuiJun CHEN LinGen LIAO NaiBing GE YanLin institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033China Hubei Provincial Engineering Technology research Center of Green Chemical equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China AECC Hunan aviation Powerplant research institute Zhuzhou 412002China

Based on a constructal theory,the structure design of a printed circuit recuperator with a semicircular heat transfer channel for supercritical CO_(2)cycle is carried ***,a complex function composed of weighted sum of the reciprocal of total heat transfer rate and total pumping power consumption is regarded as an optimization objective,and total volumes of the recuperator and heat transfer channel are regarded as *** optimal heat transfer channel radius and minimum complex function of the recuperator are *** turns out that heat transfer rate,pumping power consumption,and complex function under the optimal construct of recuperator are reduced by 15.10%,82.44%,and 32.33%,*** exists the optimal single plate channel number which results in the double minimum complex ***,for the purpose of minimizing the reciprocal of heat transfer rate and pumping power consumption,NSGA-II algorithm is used to achieve multi-objective optimization,and the minimum deviation index derived by the decision-making methods is 0.076,which can be taken as multi-objective optimal design scheme for printed circuit recuperator with semicircular heat transfer *** findings presented here can serve as theoretical recommendations for the structure design of printed circuit recuperator.

关键词： constructal theory supercritical CO_(2)cycle printed circuit heat exchanger heat transfer rate pumping power consumption multi-objective optimization

Adaptive detection of range-spread targets in homogeneous and partially homogeneous clutter plus subspace interference

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Journal of Systems Engineering and Electronics 2024年第1期35卷 43-54页

作者： JIAN Tao HE Jia WANG Bencai LIU Yu XU Congan XIE Zikeng research institute of Information Fusion Naval Aviation UniversityYantai 264001China Air Force Early Warning Academy Wuhan 430019China

Adaptive detection of range-spread targets is considered in the presence of subspace interference plus Gaussian clutter with unknown covariance *** target signal and interference are supposed to lie in two linearly independent subspaces with deterministic but unknown *** on the two-step criteria,two adaptive detectors based on Gradient tests are proposed,in homogeneous and partially homogeneous clutter plus subspace interference,*** of the proposed detectors exhibit theoretically constant false alarm rate property against unknown clutter covariance matrix as well as the power *** results show that,the proposed detectors have better performance than their existing counterparts,especially for mismatches in the signal steering vectors.

关键词： adaptive detection subspace interference constant false alarm rate Gradient test partially homogeneous environment

Improvement of Film Cooling Design for Turbine Vane Leading Edge Considering Combustor Outflow

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Journal of Thermal Science 2024年第1期33卷 311-327页

作者： WANG Xinyu LIU Cunliang FU Zhongyi LI Yang ZHU Huiren School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China AECC Hunan aviation Powerplant research institute Zhuzhou 412002China

As the interaction between the combustor and the turbine in the aero-engine continues to increase,the film cooling design considering the combustor swirling outflow has become the research *** swirling inflow and high-temperature gas first affect the vane leading edge(LE).However,no practical improved solution for the LE cooling design has been proposed considering the combustor swirling *** this paper,the improved scheme of showerhead cooling is carried out around the two ways of adopting the laid-back-fan-shaped hole and reducing the coolant outflow *** film cooling effectiveness(η) and the coolant flow state are obtained by PSP(pressure-sensitive-paint) and numerical simulation methods,*** research results show that the swirling inflow increases the film distribution inhomogeneity by imposing the radial pressure gradient on the vane to make the film excessively gather in some *** showerhead film cooling adopts the laid-back-fan-shaped hole to reduce the momentum when the coolant flows *** this cooling scheme improves the film attachment and increases the surface-averaged film cooling effectiveness(η_(sur)) by as much as15.4%,the film distribution inhomogeneity *** reducing the coolant outlet angle,the wall-tangential velocity of the coolant increases,and the wall-normal velocity *** the swirl intake condition,both ηand the film distribution uniformity are significantly increased,and the growth of η_(sur) is up to 16.5%.This paper investigates two improved schemes to improve the showerhead cooling under the swirl intake condition to provide a reference for the vane cooling design.

关键词： turbine vane showerhead cooling swirling inflow laid-back-fan-shaped hole film hole inclination

Extraction and evolution of grader’s bionic morphological feature line using shape structure behavior function model

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 74-84页

作者： Bin Qi Yubin Lan Xiaoming Sun He Zhu Yanhao Li Ke Lou College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255049ShandongChina Shandong Provincial Engineering Technology research Center for Agricultural aviation Intelligent equipment Zibo 255049China

To improve the innovation of agricultural machinery product styling,this paper proposes a shape structure behavior function(SSBF)model suitable for the industrial design *** feature line evolution method combining shape grammar and genetic algorithm was used for modelling the of the grader,which not only maintains the product style characteristics but also reflects the typical identification characteristics of the bionic prototype and produces a new product modelling *** conducting cognitive and recognition experiments on product styling features,the ranking of product styling features and the contribution of each component to product styling were *** method of combining shape grammar and quadratic Bézier curve was used to express and encode feature lines,and genetic algorithm was used to evolve biomimetic forms to form product feature lines with typical biological morphological features;The extracted form bionic elements were integrated into the grader modelling design,and the interaction evaluation was carried out through the genetic algorithm evolution *** basic form elements were extracted and analyzed,and the deduction rules were formulated and *** derived feature line geometric data considered the product’s image features and the bio-inspired prototype,which can be used for the follow-up guidance of industrial design schemes.

关键词： bionic design shape-structure-behavior-function SSBF biologically inspired design BID shape grammars Quadratic Bézier curves

Simulation of an aircraft thermal management system based on vapor cycle response surface model

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Chinese Journal of Aeronautics 2024年第6期37卷 64-77页

作者： Haodong LIU Hongsheng JIANG Sujun DONG Longxian XUE Yongji LIU Jianjun WU School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Chengdu Aircraft Design and research institute Aviation Industry Corporation of ChinaChengdu 610091China

The modern aircraft Thermal Management System(TMS)faces significant challenges due to increasing thermal loads and limited heat dissipation *** optimize TMS during the conceptual design stage,the development of a modeling and simulation tool is *** this study,a TMS simulation model library was created using MATLAB/*** simplify the complexity of the Vapor Cycle System(VCS)model,a Response Surface Model(RSM)was constructed using the Monte Carlo method and validated through simulation *** the F-22 fighter TMS as an example,a thermal dynamic simulation model was constructed to analyze the variation of thermal response parameters in key subsystems and elucidate their coupling ***,the impact of total fuel flow and ram air flow on the TMS was *** findings demonstrate the existence of an optimal total fuel flow that achieves a balance between maximizing fuel heat sink utilization and minimizing bleed air *** adaptive distribution of fuel and ram air flow was found to enhance aircraft thermal management *** study contributes to improving modeling efficiency and enhancing the understanding of the thermal dynamic characteristics of TMS,thereby facilitating further optimization in aircraft TMS design.

关键词： Thermal management sys-tem Vaporcycle Response surface model Dynamic simulation MonteCarlo

Simultaneous Identification of Thermophysical Properties of Semitransparent Media Using a Hybrid Model Based on Artificial Neural Network and Evolutionary Algorithm

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期41卷 458-475页

作者： LIU Yang HU Shaochuang Sino-European institute of aviation Engineering Civil Aviation University of ChinaTianjin 300300P.R.China

A hybrid identification model based on multilayer artificial neural networks(ANNs) and particle swarm optimization(PSO) algorithm is developed to improve the simultaneous identification efficiency of thermal conductivity and effective absorption coefficient of semitransparent *** the direct model,the spherical harmonic method and the finite volume method are used to solve the coupled conduction-radiation heat transfer problem in an absorbing,emitting,and non-scattering 2D axisymmetric gray medium in the background of laser flash *** the identification part,firstly,the temperature field and the incident radiation field in different positions are chosen as ***,a traditional identification model based on PSO algorithm is ***,multilayer ANNs are built to fit and replace the direct model in the traditional identification model to speed up the identification *** results show that compared with the traditional identification model,the time cost of the hybrid identification model is reduced by about 1 000 ***,the hybrid identification model remains a high level of accuracy even with measurement errors.

关键词： semitransparent medium coupled conduction-radiation heat transfer thermophysical properties simultaneous identification multilayer artificial neural networks(ANNs) evolutionary algorithm hybrid identification model

Interface strengthening for thermal sprayed WC-10Co4Cr coating subjected to pulsed magnetic treatment

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Rare Metals 2024年第2期43卷 780-795页

作者： Cheng-Kai Qian Qu Liu Heng Wang Ke-Jian Li Zhi-Peng Cai Department of Mechanical Engineering Tsinghua UniversityBeijing100084China Tianjin research institute for Advanced equipment Tsinghua UniversityTianjin300304China State Key Laboratory of Tribology in Advanced equipment Tsinghua UniversityBeijing100084China

The reliability of the coated industry components demands ideal fatigue properties of the coating,and it is mainly determined by the performance of the *** this study,pulsed magnetic treatment(PMT)was applied to the thermal sprayed WC-10Co4Cr coating,and the fatigue lifetime of the coated bolt increased by 219.82%under an imitation of the operating mode *** tests further proved that both the adhesion and cohesion strength were improved after PMT,and they benefit from the interface strengthening *** formation of coherent WC/Co interfaces was characterized by in-situ transmission electron microscopy(TEM),and the molecular dynamic simulations indicate that the work of separation of these interfaces is much higher than the original disordered *** stress was relaxed and distributed more homogeneously after PMT,and it mainly contributes to the coating/substrate *** work provides a new post-treatment method focusing on the interfaces in the WC-based coating and gives insight into its mechanism so that it is hopeful to be applied to other kinds of coatings.

关键词： Cemented carbide coating Pulsed magnetic treatment Interface strengthening Fatigue properties Adhesion strength

Nonlinear Impact Damage Evolution of Charpy Type and Analysis of Its Key Influencing Factors

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 254-264页

作者： Jianfeng Mao Qian Xu Jiadong Yang Chi Cao Dasheng Wang Fengping Zhong Mingya Chen institute of Process equipment and Control Engineering Zhejiang University of TechnologyHangzhou 310032China Taizhou Key Laboratory of Advanced Manufacturing Technology Taizhou InstituteZhejiang University of TechnologyTaizhou 318014China State Key Laboratory of Nuclear Power Safety Monitoring Technology and equipment Shenzhen 518172China Zhejiang Academy of Special equipment Science Hangzhou 310020China Suzhou Nuclear Power research institute Suzhou 215004China

The current research of Charpy impact mainly focuses on obtaining the ductile brittle transition temperature of materials by *** with experiments,numerical simulation can study many problems with harsh ***,there are still few studies on the influence of geometric factors such as side *** this paper,the geometry of standard Charpy impact test is *** with different widths and side grooves are *** finite element model of Charpy impact was established by ABAQUS *** test results and simulation results to verify each *** effects of sample width,side groove depth and side groove bottom fillet on the impact fracture resistance of the sample were *** results show that the specimen width is positively correlated with the impact toughness of the *** side groove greatly reduces the impact toughness of the material;the toughness of side groove decreases with the increase of depth;the fracture toughness of side groove decreases with the increase of fillet at the bottom of side *** proportion of toughness energy to impact energy of samples was *** results show that the toughness energy accounts for about 70%of the impact energy of the sample,which has little to do with the geometric characteristics of the *** study presents a reliable method for studying Charpy impact *** influence of geometric parameters is obtained,which provides a reference method for the study of impact toughness of high toughness materials.

关键词： Johnson-Cook model Impact toughness Charpy impact