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QUANTITATIVE RELATION BETWEEN YIELD STRESS AND R-VALUE OF Ti PLATE ALONG PARALLEL AND PERPENDICULAR TO ROLLING DIRECTION

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Acta Metallurgica Sinica(English Letters) 1990年第9期3卷 196-199页

作者： ZHANG Derong shenyang institute of aeronautical engineering,shenyang,China ZHANG Derong Associate Professor.Dept.of {2.,shenyang institute of aeronautical engineering,shenyang 110031,China

An attempt was made on the quantitative prediction of the relationship hetween the yield stress and R-value along the parallel and perpendicular to the rolling direction of Ti plate based on analysis of the previous experimental *** is shown that the yield stress along one direction and another is quite synchronized with the R—*** to the plasticity theo- ry,an formular of σ_(1s)/σ_(2.)=[(1+1/R_2./(1+1/R_1)/^(1 2. was proposed,In statistic estima- *** calculated results are in good agreement with the experimental *** availability of this formula was briefly discussed also.

关键词： titanium plate yield stress R-value

New development thoughts on the bio-inspired intelligence based control for unmanned combat aerial vehicle

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Science China(Technological Sciences) 2010年第8期53卷 2025-2031页

作者： DUAN HaiBin 1 ,SHAO Shan 2.,SU BingWei 3 &ZHANG Lei 41 State Key Laboratory of Science and Technology on Holistic Flight Control,school of Automation Science and Electrical engineering, Beijing University of {2. and astronautics,Beijing 100191,China 2.Flight Control Department,shenyang Aircraft Design and Research institute,shenyang 110035,China 3 Beijing institute of Near Space Vehicle’s System engineering,Beijing 100076,China 4Integration and Project Section,Air Force Equipment Academy,Beijing 100085,China 1. State Key Laboratory of Science and Technology on Holistic Flight Control School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China2. Flight Control Department Shenyang Aircraft Design and Research Institute Shenyang 110035 China3. Beijing Institute of Near Space Vehicle’s System Engineering Beijing 100076 China4. Integration and Project Section Air Force Equipment Academy Beijing 100085 China

Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of *** the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.

关键词： bio-inspired intelligence unmanned combat aerial vehicle(UCAV) artificial brain autonomous control bayesian network bio-inspired hardware heterogeneous cooperative control

Optimization design study of low-Reynolds-number high-lift airfoils for the high-efficiency propeller of low-dynamic vehicles in stratosphere

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Science China(Technological Sciences) 2010年第10期53卷 2792-2807页

作者： MA Rong1, ZHONG BoWen2.& LIU PeiQing1 1 Key Laboratory of Fluid Mechanics, Ministry of Education, institute of Fluid Mechanics, school of {2. Science and engineering, Beijing University of aeronautics and astronautics, Beijing 100191, China 2.Department of Aerospace Science, school of engineering, Cranfield University, MK43 0AL, United Kingdom 1. Key Laboratory of Fluid Mechanics Ministry of Education Institute of Fluid Mechanics School of Aeronautical Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China2. Department of Aerospace Science School of Engineering Cranfield University MK43 0AL Cranfield UK

Aerodynamic performance of low-Reynolds-number high-lift airfoil makes a great impact on designing a high-efficiency propeller for low-dynamic vehicles in stratosphere. At high altitude,low-Reynolds-number airfoils are supposed to have high lift-drag ratio or high endurance factor at cruising attack angle along with good stall characteristics. To design such a high-performance low-Reynolds-number high-lift airfoil,the paper established a hierarchical multi-objective optimization platform by combing direct search optimization algorithm EXTREM and airfoil flow field solver XFOIL to automatically and quickly calculate aerodynamic performance function of airfoil by computer. It provides an effective solution to multi-point design problem of low-speed low-Reynolds-number airfoil. It can be seen from the results of three typical optimization examples,the new airfoil E387_OPT2.FX63-137_OPT2.and S12.3_OPT2.based on hot low-Reynolds-number high-lift airfoils (Eppler 387 airfoil,Wortmann FX63-137 airfoil and S12.3 airfoil) can meet the optimization design requirements and have very good aerodynamic characteristics in both design state and non-design state. Thus,the applicability and effectiveness of hierarchical multi-objective optimization platform are verified.

关键词： multi-objective optimization low Reynolds number airfoil EXTREM hierarchical multi-objective optimization

Shape Character of Fusion-solidification Zone of EBW Joints for Titanium Alloy

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稀有金属材料与工程 2011年第S4期40卷 74-78页

作者： Fu Pengfei1,2.Mao Zhiyong2.Wang Yajun3,Gong Shuili2.Liu Xin2.1school of Materials Science and engineering,Huazhong University of Science and Technology,Wuhan 430074,China 2.cience and Technology on Power Beam Processes Laboratory,Beijing {2. Manufacturing Technology Research institute,Beijing 10002.,China3school of Mechanical engineering and Automation,Beijing University of aeronautics and astronautics,Beijing 100191,China Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China Huazhong Univ Sci & Technol Sch Mat Sci & Engn Wuhan 430074 Peoples R China Beijing Univ Aeronaut & Astronaut Sch Mech Engn & Automat Beijing 100191 Peoples R China

Shape character of fusion-solidification zone of electron beam welding (EBW) joints was studied for TC4 *** typical shapes of the fusion-solidification zone were gained by appropriate welding *** shapes and dimensions of the fusion-solidification zone of TC4 titanium joints were apparently influenced by processing parameters,focusing state and power density *** on the analyses of processing parameters,focusing state and power density distribution,the integrated parameters of n1 and n2.were put forward,which represented the distribution and intensity of electron beam *** a series of the formulations are developed to predict the shape of fusion-solidification zone by the processing parameters.

关键词： electron beam welding (EBW) titanium alloy fusion-solidification zone mathematical model

Study on Ultra-sonic Frequency Pulse TIG of Titanium Alloy

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稀有金属材料与工程 2011年第S3期40卷 259-262页

作者： Zhou Shuiliang1, Zhao Haitao1, Qi Bojin 2.1 Beijing aeronautical Manufacturing Technology Research institute, aeronautical Key Laboratory for Aviation Joining Technology, Beijing 10002., China 2.eijing University of aeronautics & astronautics, Beijing 100191, China Beijing Aeronaut Mfg Technol Res Inst Aeronaut Key Lab Aviat Joining Technol Beijing 100024 Peoples R China Beijing Univ Aeronaut & Astronaut Beijing 100191 Peoples R China

Ti-6Al-4V alloy is used extensively in aerospace and aircraft because of its excellent comprehensive properties and outstanding machinability. Ti-6Al-4V alloy was welded by conventional tungsten iner-gas arc welding (TIG) and ultra-sonic frequency pulse TIG welding (U-TIG) respectively. The welding quality was tested by X-ray, and the mechanical properties of welded joint were tested , the microstructure and the fracture appearance of welded joint were observed by means of optical microscope and SEM .The results show that the joints were welded successfully by U-TIG welding, U-TIG welding could reduced pores defects of welded joint. With the increment of ultra-sonic pulse frequency, the microstructure became more and more fine and was inclined to equiaxed crystal. Moreover, the properties of joint by U-TIG welding were improved compared with that of conventional TIG. Tensile fractures of joints by TIG welding and U-TIG welding all presented character of quasi-cleavage crack, but the cellular dendrite depredation was not observed obviously in U-TIG joint.

关键词： ultra-sonic frequency pulse TIG welding tungsten iner-gas arc welding titanium alloy

Performance comparison and parametric study on spiral groove gas film face seals

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Science China(Physics,Mechanics & Astronomy) 2004年第z1期47卷 29-36页

作者： LIU Yuchuan, SHEN Xinmin, XU Wanfu & WANG ZhiliState Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China school of Mechanical engineering and Automation, Beijing University of {2. and astronautics, Beijing 100083, China Lubrication Technology Research Center, shenyang institute of Technology, shenyang 110015, China Tsing Hua Univ State Key Lab Tribol Beijing 100084 Peoples R China Beijing Univ Aeronaut & Astronaut Sch Mech Engn & Automat Beijing 100083 Peoples R China shenyang Inst Technol Lubricat Technol Res Ctr Shenyang 110015 Peoples R China

Several spiral groove gas film face seals (SGFS) with different layouts are compared quantitatively to analyze their merits and faults and application behaviors. In addition, a parametric study on downstream mode SGFS is conducted to determine its optimal parameters under certain working conditions. In tne computation of gas film pressure on the face, finite element method (FEM) is applied to adapt to complicated geometrical boundary.

关键词： spiral groove, gas film face seals, parameter study, performance comparison, finite element method.

Influences of Laser Powers on Microstructure and Properties of the Al-Si/Al+Al_2._3 Coating on the AZ91D Magnesium Alloy

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稀有金属材料与工程 2011年第S4期40卷 226-230页

作者： Qian Jiangang1,Zhang Jiaxiang1,2.Li Shuqing2.Wang Chun2.Gong Shuili2.school of Chemistry and Environment,Beijing University of aeronautics and {2.,Beijing 100191,China2.cience and Technology on Power Beam Processes Laboratory,Avic Beijing aeronautical Manufacturing Technology Research institute,Beijing 10002.,China Beijing Univ Aeronaut & Astronaut Sch Chem & Environm Beijing 100191 Peoples R China Avic Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

An Al-Si/Al+Al2.3 coating was prepared on an AZ91D Mg alloy substrate by laser cladding of the plasma-sprayed coating.X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to identify the phases and to study the morphology,*** adhesion strength and the porosity ratio of the coating were measured by using a tensile testing machine and an optical microscope (OM),*** microhardness was measured using a micro Vickers hardness *** results show that after laser cladding,the adhesion strength of the coating increased from 10.78 to 2..17 *** the laser power was 1400W,the metastable γ-Al2.3 phase in the coating transformed completely into the stable α-Al2.3 *** with the increase of the laser power,the porosity ratio of the coating *** when the laser power was over 1400W,the porosity ratio *** microhardness of the surface was the hardest which was improved from HV0.0512. to *** larger the power of the laser was,the harder the coating *** when the power was 1600W,the microhardness increased slightly,even the microhardness of the internal decreased.

关键词： laser-clad plasma-sprayed magnesium alloy Al-Si/Al+Al2.3 coating

Distributed optimization using virtual and real game strategies for multi-criterion aerodynamic design

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Science China(Technological Sciences) 2008年第11期51卷 1939-1956页

作者： TANG ZhiLi1, BAI Wen2.& DONG Jun3 1 College of Aerospace engineering, Nanjing University of aeronautics & {2., Nanjing 2.0016, China 2.Chinese aeronautics Computation Technique Research institute, Xi’an 710068, China 3 Chinese Aerodynamic Research institute on aeronautics, shenyang 110034, China College of Aerospace engineering Nanjing University of Aeronautics & Astronautics Nanjing 210016 China Chinese aeronautics Computation Technique Research institute Xi’an 710068 China Chinese Aerodynamic Research institute on aeronautics Shenyang 110034 China

This paper introduces the virtual and real game concepts to investigate multi-criterion optimization for optimum shape design in aerodynamics. The constrained adjoint meth- odology is used as the basic optimizer. Furthermore, the above is combined with the vir- tual and real game strategies to treat single-point/multi-point airfoil optimization. In a symmetric Nash Game, each optimizer attempts to optimize one’s own target with ex- change of symmetric information with others. A Nash equilibrium is just the compromised solution among the multiple criteria. Several kinds of airfoil splitting and design cases are shown for the utility of virtual and real game strategies in aerodynamic design. Successful design results confirm the validity and efficiency of the present design method.

关键词： multi-criterion optimization Nash equilibrium virtual game real game aerodynamics distributed computing

Application of median filter technique and ESP in PSP data processing

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Application of median filter technique and ESP in PSP data p...