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Effects of radiation heat transfer space non-uniformity of combustion chamber components on in-cylinder soot emission formation in diesel engine

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Science china(Technological Sciences) 2010年第7期53卷 1824-1832页

作者： Lü JiZu1, BAI MinLi2 & LI XiaoJie1 1 State Key Laboratory of Structural Analysis for Industrial Equipment, dalian university of Technology, dalian 116023. {3. 2 School of Energy and Power Engineering, dalian university of Technology, dalian 116023. {3. 1. State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116023 China2. School of Energy and Power Engineering Dalian University of Technology Dalian 116023 China

Combustion chamber components (cylinder head-cylinder liner-piston assembly-fuel film) were treated as a coupled body. Based on the three-dimensional numerical simulation of heat transfer of the coupled body, the multi-dimensional simulation computation coupling flow and solid on working process and combustion chamber components of internal combustion engine was performed using Discrete Transfer Radiation Model (DTRM) radiation heat transfer model, zoning solution method and boundary coupling method. The simulation was applied to the influence investigation of the space non-uniformity in radiation heat transfer among combustion chamber components on the generation of in-cylinder soot emissions. The results show that the space non-uniformity in heat transfer among the combustion chamber components has great influence on the generation of in-cylinder NOx emissions. The difference value of total soot in cylinder when exhaust valves are opened is 1.3. (no radiation), 0.8% (radiation). So the effect of radiation heat transfer space non-uniformity of combustion chamber components on total soot production can be ignored. While in local area radiation heat transfer space non-uniformity has certain effect on soot production inside whole combustion chamber space, and has less effect on soot production in the area near the wall of combustion chamber components.

关键词： radiation heat transfer space non-uniformity in-cylinder diesel engine

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Air Target Fuzzy Pattern Recognition Threat-Judgment Model

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Journal of Systems Engineering and Electronics 2003年第1期14卷 41-46页

作者： Tong Youtang & Wang Jianmingdalian university of Technology, dalian 110624, P. R. {3. dalian Naval Academy, dalian 116018, P. R. {3. dalian university of Technology Dalian 110624 P. R. China dalian Universiry of Technology Dahan 110624 P. R. China dalian Universiry of Technology Dahan 110624 P. R. China

Threat-judgment is a complicated fuzzy inference problem. Up to now no relevant unified theory and measur-ing standard have been developed. It is very difficult to establish a threat-judgment model with high reliability in the airdefense system for the naval warships. Air target threat level judgment is an important component in naval warship com-bat command decision-making systems. According to the threat level judgment of air targets during the air defense of sin-gle naval warship, a fuzzy pattern recognition model for judging the threat from air targets is established. Then an algo-rithm for identifying the parameters in the model is presented. The model has an adaptive feature and can dynamicallyupdate its parameters according to the state change of the attacking targets and the environment. The method presentedhere can be used for the air defense system threat judgment in the naval warships.

关键词： Air targets Threat judgment Fuzzy pattern recognition Fuzzy sets

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Expansive Behaviors of Self-stressing Concrete under Different Restraining Conditions

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Journal of Wuhan university of Technology(Materials Science) 2011年第4期26卷 780-785页

作者：常旭 College of Civil Engineering Henan Polytechnic University

The expansive behaviors of the expensive concrete under different restraining conditions were systemically studied. The experimental results indicate that expansive deformation obviously increases before 10 days and tends to be constant after 25 days regardless of the restraining conditions. The mixture ratio of expansive cement and restraining conditions are the main factors affecting expansive deformation. Self-stress can be obtained when the expansive deformation is restrained. The higher self-stress could be obtained when the expensive concrete is restrained by steel tube. For specimens under steel tube restraining, the wall thickness and the length of the steel tube have important influence on self-stress. Both the radial self-stress and axial self-stress in concrete core increase when wall thickness or length of the steel tube increases.

关键词： self-stress expansive concrete restraining condition

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Neuroprotection of aucubin in primary diabetic encephalopathy

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Science china(Life Sciences) 2008年第6期51卷 495-502页

作者： XUE HongYu1, JIN LiJi1,2, JIN Lei1, ZHANG Peng1, LI DanQing4, XIA YanQiu1, LU YaNan1 & XU YongPing1,3.1 Department of Bioscience and Biotechnology, dalian university of Technology, dalian 116024, {3. 2 State Key Laboratory of Fine Chemicals, dalian university of Technology, dalian 116024, {3. 3.dalian SEM Bioengineer and Biotech Ltd., dalian 116024, {3. 4 The Second Affiliated Hospital, dalian Medical university, dalian 116024, {3. 1. Department of Bioscience and Biotechnology Dalian University of technology Dalian 116024 China 2. State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 China 4. The Second Affiliated Hospital Dalian Medical University Dalian 116024 China 3. dalian SEM Bioengineer and Biotech Ltd. Dalian 116024 China

Hippocampal neuronal apoptosis accompanied by impairment of cognitive function occurs in primary diabetic encephalopathy. In this study, we investigated the neuroprotective mechanism of the iridoid glycoside, aucubin, using rats (n=8). Diabetes mellitus was induced in the rats by intraperitoneal (i.p.) injection of streptozotocin (60 mg/kg body weight). After 65 d, half of the DM rats were administered aucubin (5 mg/kg; i.p.) for 15 d, yielding treatment DM+A. A third group of rats received no strepto- zotocin or aucibin, and served as controls (CON). Encephalopathy was assessed using Y-maze be- havioral testing. Rats were euthanized on Day 87, and hippocampi were excised for visual (light and transmission electron microscopic) and immunochemical (Western blot; immunohistochemical) as- sessments of the CA1 subfield for apoptosis and expression of regulatory proteins Bcl-2 and Bax. Treatment responses to all the parameters examined (body weight, plasma glucose, Y-maze error rates, pyramidal cell ultrastructure, proportions of apoptotic cells, levels of expression of Bcl-2 and Bax, and survivability of neuronal cells) were identical: there were highly significant differences between DM and CON groups (P<0.001), but the effects were significantly moderated (P<0.01) in DM+A compared with DM. These findings confirm the association of apoptosis with the encephalopathic effects of diabetes mellitus, and suggest a major role of the expression levels of Bcl-2 and Bax in the regulation of apop- totic cell death. All of the results suggest that aucubin could effectively inhibit apoptosis by modulating the expressions of Bcl-2 and Bax genes.

关键词： aucubin diabetic encephalopathy neuroprotection apoptosis hippocampus

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A modified method for simulating non-stationary multi-point earthquake ground motion

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 201-211页

作者： Li Minggao,Li Xin and Zhou Jing State Key Laboratory of Coastal and Offshore Engineering,dalian university of Technology,dalian 116024,{3. State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

A spectral-representation-based algorithm is proposed to simulate non-stationary and stochastic processes with evolutionary power,according to a prescribed non-stationary cross-spectral density matrix. Non-stationary multi-point seismic ground motions at different locations on the ground surface are generated for use in engineering applications. First,a modified iterative procedure is used to generate uniformly modulated non-stationary ground motion time histories which are compatible with the prescribed power spectrum. Then,ground motion time histories are modeled as a non-stationary stochastic process with amplitude and frequency modulation. The characteristic frequency and damping ratio of the Clough-Penzien acceleration spectrum are considered as a function of time in order to study the frequency time variation. Finally,two numerical examples are presented to validate the efficiency of the proposed method,and the results show that this method can be effectively applied to the dynamic seismic analysis of long and large scale structures.

关键词： multi-support excitation spatial correlation power spectrum-compatibility non-stationary ground motion simulation

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A disjoint algorithm for seismic reliability analysis of lifeline networks

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Earthquake Engineering and Engineering Vibration 2002年第2期1卷 207-212页

作者： Han Yang dalian university of Technology,dalian 116023.{3. SUN Shaoping Beijing Municipal Engineering Research Institute,Beijing 10003.,{3. Senior Engineer dalian university of Technology Dalian China Beijing Municipal Engineering Research Institute Beijing China

The algorithm is based on constructing a disjoin kg t set of the minimal paths in a network *** this paper, cubic notation was used to describe the logic function of a network in a well-balanced state,and then the sharp-product operation was used to construct the disjoint minimal path set of the network.A computer program has been developed,and when combined with decomposition technology,the reliability of a general lifeline network can be effectively and automatically calculated.

关键词： lifeline network reliability disjoint product DFS algorithms logic function sharp-product

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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, Xi’an 710069, china 2. The Geological Lab Center, china university of Geosciences (Beijing), Beijing 100083. china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, Peking university, Beijing 100871, china 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 16-25页

作者： LU Lin1,2,TENG Bin3.CHENG Liang 4,SUN Liang5 & CHEN XiaoBo6 1 Center for Deepwater Engineering,dalian university of Technology,dalian 116024,{3. 2 State Key Laboratory of Structural Analysis for Industrial Equipment,dalian university of Technology,dalian 116024,{3. 3.State Key Laboratory of Coastal and Offshore Engineering,dalian university of Technology,dalian 116024,{3. 4 School of Civil and Resource Engineering,The university of Western Australia,Crawly 6003.Australia 5 Centre for Offshore Research and Engineering,Department of Civil Engineering,National university of Singapore,117576,Singapore 6 Research Department,Bureau Veritas,Neuilly-Sur-Seine,92570,France 1. Center for Deepwater Engineering Dalian University of Technology Dalian 116024 China2. State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China3. State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China4. School of Civil and Resource Engineering The University of Western Australia Crawly 6003 Australia5. Centre for Offshore Research and Engineering Department of Civil Engineering National University of Singapore Singapore 117576 Singapore6. Research Department Bureau Veritas Neuilly-Sur-Seine 92570 France

Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water *** numerical results are compared with experimental data available in the *** comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the resonant frequency reasonably *** the conventional potential flow model(without artificial damping term) significantly over-predicts the wave height in narrow gaps around the resonant *** order to calibrate the appropriate damping coefficient used for the potential model and make it work as well as the viscous fluid model in predicting the resonant wave height in narrow gaps but with little computational efforts,the dependence of damping coefficient μ on the body geometric dimensions is examined considering the parameters of gap width Bg,body draft D,body breadth ratio Br and body number n(n = 2,3.,where Br = BB/BA for the case of two bodies(Body A and Body B) with different breadths of BA and BB,*** was confirmed that the damping coefficient used for the potential flow model is not sensitive to the geometric dimensions and spatial *** was found that μ∈ [0.4,0.5] may guarantee the variation of Hg/H0 with kh to be generally in good agreement with the experimental data and the results of viscous fluid model,where Hg is the excited wave height in narrow gaps under various dimensionless incident wave frequencies kh,H0 is the incident wave height,k = 2π/L is the wave number and h is the water depth.

关键词： narrow gap fluid resonance water wave viscous fluid model potential flow model finite element method boundary element method

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Online diagnosis of electron excitation temperature in CH_4+H_2 discharge plasma at atmospheric pressure by optical emission spectra

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Science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1892-1896页

作者： CUI JinHua1, XU ZhenFeng2, ZHANG JiaLiang3., NIE QiuYue3. XU GenHui4 & REN LongLiang5 1 Faculty of Chemistry and Chemical Engineering, Liaoning Normal university, dalian 116021, china 2 Technique Center for Modern Education, Liaodong College, Dandong 126709, china 3.State Key Laboratory for Materials Modification by Laser, Ion and Electron Beams, dalian university of Technology, dalian 116023. china 4 College of Chemical Engineering, Tianjin university, Tianjin 3.0072, china 5 Department of Physics, Science College, Tianjin university, Tianjin 3.0072, china 1. Faculty of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116021 China 2. Technique Center for Modern Education Liaodong College Dandong 126709 China 3. State Key Laboratory for Materials Modification by Laser Ion and Electron Beams Dalian University of Technology Dalian 116023 China 4. College of Chemical Engineering Tianjin University Tianjin 300072 China 5. Department of Physics Science College Tianjin University Tianjin 300072 China

Methane coupling under low temperature plasmas at atmospheric pressure is a green process by use of renewable sources of energy. In this study, CH4+H2 dis- charge plasma was on-line diagnosed by optical emission spectra so as to char- acterize the discharge system and to do spade work for the optimization of the technical parameters for future commercial production of methane coupling under plasmas. The study was focused on a calculation method for the online diagnosis of the electron excitation temperature in CH4+H2 discharge plasma at atmospheric pressure. The diagnostic method is easy, efficient and fairly precise. A serious er- ror in a literature was corrected during the reasoning of its series of equations formerly used to calculate electron temperatures in plasmas.

关键词： low temperature plasma electron excitation temperature optical emission spectrum online diagnosis

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Experimental remolding on the caprock's 3. strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area

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Science china Earth Sciences 2005年第7期48卷 863-874页

作者： DENG Jun1,HUANG Dinghua2,WANG Qingfei1,WAN Li1,SUN Zhongshi3.YANG Liqiang1 & GAO Bangfei1 1. State Key Laboratory of Geological Processes and Mineral Resources,china university of Geosciences,Beijing 100083.china 2. Faculty of Earth Sciences,china university of Geosciences,Wuhan 43.074,china 3. Department of Earth Sciences,Jilin university,Changchun 13.061,china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Department of Earth Sciences Jilin University Changchun 130061 China

Based on field observations and rheology analysis, we perform one analogue experiment and remold the 3. structural frame of Tongling deposit concentrating area firstly. Then we disassemble and dialyze the 3. structures of the model using the methods of "slicing" and "stripping". A series of sliced planes vertical to the fold hinges show similar landscapes of that in the drill hole profiles. Meanwhile, layer stripping analysis indicates that the deformation features of each layer in the model are qualitatively analogical to those obtained from field observations. Through contrasting the 3. structure between the experimental model and the field phenomena, we verify the following 3. deformation features of the caprock in this area: (1) the Tongling area mainly consists of three series of NE S-typed fold groups; (2) in the uniform stress field, the incoherent folds universally develop in different positions, along different axes as well as in different strata; (3. the faults propagate upward which are mostly inter-bedded detachment faults, while the fold amplitudes decrease while going deeper; and (4) the folds and cleavages are highly developed in the Silurian System indicating that the deformation effect of the Indosin-ian-Yanshanian structural layer terminates at this layer, which suggests that the Silurian System is the crucial layer for the inversion between brittle and plastic deformation domains and the underlying strata are subject to the control of another deformation system with distinct properties.

关键词： Tongling deposit concentrating area Indosinian-Yanshanian epoch 3. structural frame of the caprock analogue experiment slicing and stripping analysis structural model.

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