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⊙第81篇⊙

自錨式懸索橋撓度理論基礎微分方程近似推導
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注意:本論文已在《哈爾濱工業大學學報》2004,36(12):1733-1735發表
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EI已經收錄本文)
石磊 劉春城 張哲
(大連理工大學土木水利學院,大連 116024 )

摘 要: 基于大位移非線性彈性理論的廣義變分原理,考慮了加勁梁軸向壓縮應變能的影響,建立了三跨自錨式懸索橋撓度理論下的大位移不完全廣義勢能泛函,通過約束變分導出了自錨式懸索橋撓度理論下的基礎微分方程,得出了自錨式懸索橋撓度理論的基礎微分方程近似于彈性理論下的微分方程這一結論.為闡述自錨式懸索橋靜力行為提供了理論依據. 
關鍵詞: 自錨式懸索橋 撓度理論 泛函 廣義變分

The Basic Differential Equation Deductive of the Self-anchored Suspension Bridge

SHI Lei ,ZHANG Zhe, LIU Chun-cheng
(Institute of Civil & Hydraulic Engineering, Dalian University of Technology,
Dalian, 116024)

Abstract: Based on the generalized potential energy variational principal of nonlinear elasticity theory with large deflection, the incomplete generalized potential energy function with large deflection is established based on the flexibility theory of three-span self–anchored suspension bridge by considering the effect of axial compressive energy of stiffening girder. By constraint variation, the differential equations under flexibility theory is closed to the elastic theory vibration have been derived. It can provide theoretical basis for the static analysis of self-anchored suspension bridge。
Keywords: Self-Anchored suspension bridge, flexibility theory, functional, generalized variation


⊙第82篇⊙

釘肋肋列傳熱的最小熵產優化分析
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注意:本論文已在《高校化學工程學報》1999,13(4):309-314發表
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蘇亞欣 駱仲泱 岑可法 倪明江
( 浙江大學熱能工程研究所,杭州,310027 )

摘 要: 本文應用熱力學的熵產概念對釘肋肋列的傳熱問題進行了研究,從如何使各種不可逆損失最小著手,分析了肋列的肋間距、肋片的直徑、換熱介質與熱負荷等不同參數對熵產的影響,發現在不同參數條件下,熵產數都會存在一個最小值以及與此對應的最優的Red,opt數,并對順列和錯列兩種常用肋片布置方式作了對比。研究結果將有助于節能型釘肋的設計。. 
關鍵詞: 釘肋肋列 不可逆損失 熵產優化

An analysis on the heat transfer of pin fin array of minimum entropy generation

Yaxin Su Zhongyang Luo Kefa Cen Mingjiang Ni
( Institute of Thermal Power Engineering, Zhejiang University , Hangzhou, 310027 )

Abstract: In this paper , the thermodynamic concept of entropy generation is applied to study the heat transfer of an array of pin fins . Beginning with the minimization of variable irreversibility, an analysis is made on the influence of the parameters such as pin spacing , pin diameter, the property of heat transfer fluid, heat duty et al . It’s found that all the dimensionless entropy generation number will have a minimum value under different parameters and a corresponding optimal Reynolds number Red,opt exists. A comparison of an in-line and staggered pin fin array is made . The results will be helpful for the design of pin fins that conserve more available work.
Keywords: pin fin array; irreversibility; entropy generation minimization


⊙第83篇⊙

方形分離器內部兩相流場的PDA實驗研究
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注意:本論文已在《中國電機工程學報》2001,21(2):42-45發表
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蘇亞欣 周勁松 駱仲泱 岑可法
(浙江大學熱能工程研究所,杭州,310027)

摘 要: 應用三維顆粒動態分析儀(3D-PDA)對方形下排氣分離器內的氣固兩相流場進行了測試,得到了幾種工況條件下的流場矢量分布。研究發現分離器方腔內的流場偏離其幾何中心,并呈中間為強旋流動和邊壁附近為弱旋的準自由渦區的特點,且在邊角處存在局部小旋渦。不等溫流場比等溫流場要均勻一些,但旋流強度減弱,分離效率降低。研究結果對于分析分離器的分離機理和結構優化有一定的指導意義。 
關鍵詞: 方形下排氣旋風分離器 氣固兩相流 3D-PDA

An experimental study on the gas-solid two-phase flow in a square cyclone separator with downward gas exit by 3D-PDA

SU Yaxin ZHOU Jinsong LUO Zhongyang CEN Kefa
( Institute of Thermal Power Engineering, Zhejiang University, Hangzhou, 310027 )

Abstract: Three dimensional Particle Dynamic Analyzer (3D-PDA) was employed to measure the gas-solid two-phase flow in a lab-scale square cyclone separator with downward gas exit under 4 cases of different inlet velocity and particle concentration. The particle used in the test was glass beard of mean diameter 30~40mm. It's found that the center of the flow field deviated from the geometric center of the cyclone. The flow fields showed a feature of Rankine eddy, i.e. strongly swirling region in the central part and pseudo-free eddy region of weak swirling intensity near the cyclone wall. Local vortex existed at the corners where the flow changed its direction sharply. When the cyclone wall was heated and the suspension temperature was elevated, it's found that the flow field became more uniform than that under room-temperature condition. The local vortex at the corners were weakened and the swirling intensity became poorer which led to a decreased total mean separation efficiency from about 81% to 76.5%. The results of this paper provide a further understand of the separation mechanism and guidance for the optimization of the square cyclone separator structure.
Keywords: square cyclone separator with downward; gas exit gas-solid suspension; 3D-PDA


⊙第84篇⊙

循環流化床顆粒團更新傳熱模型的修正
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注意:本論文已在《動力工程》2001,21(5):1426-1429,1416發表
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蘇亞欣 駱仲泱 岑可法
(浙江大學熱能工程研究所,杭州,310027)

摘 要: 對顆粒團更新傳熱模型做了修正,引入新的床內流動特性的研究結果,改進了顆粒團覆蓋壁面的百分比和顆粒團—壁面之間的氣膜厚度的表達式,使之與床的宏觀運行參數以及床體、床料的參數相聯系,從而避免了前人模型中憑經驗來確定一個比例系數的缺陷。對于彌散相和壁面間的輻射傳熱,考慮到了它們的直接輻射和彌散相輻射到顆粒團、再經顆粒團反射到壁面的傳遞過程。模型計算結果和有關實驗數據的對比吻合較好,說明本文的修正模型是合理的。
 
關鍵詞: 循環流化床 傳熱模型 修正

Modification to the CFB Cluster-Renewal Heat Transfer Model

Yaxin Su Zhongyang Luo Kefa Cen
( Institute of Thermal Power Engineering, Zhejiang University, Hangzhou, 310027 )

Abstract: Based on the Cluster Renewal Model of the particle motion in a CFB riser, the authors developed a revised heat transfer model, which introduced the latest research results of the hydrodynamics of the suspension flow in CFB. This model divided the heat transfer into two parts, which are due to the transient heat conduction by the covered clusters and the convection between the uncovered wall and the dispersed phase. Radiation at high temperature was regarded as being additive. The fraction of the covered wall by clusters and the thickness of the gas gap between clusters and wall were revised by a new formula, which is a function of the operating condition and the particle properties. The Radiation between the dispersed phase and the uncovered wall included not only the direct radiation to the uncovered wall, but also the radiation to the clusters and then reflected to the uncovered wall. The model results showed good agreement with the published experimental data, which proved the modification was reasonable.
Keywords: circulating fluidized bed heat transfer model modification


⊙第85篇⊙

方形冷卻型分離器內壁面和兩相流間的傳熱理論模型
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注意:本論文已在《中國電機工程學報2001》2001,21(12):100-104發表
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蘇亞欣1 駱仲泱2 岑可法2
(1:東華大學環境科學與工程學院,上海,200051;2:浙江大學熱能工程研究所,杭州,310027)

摘 要: 對方形冷卻型分離器內的傳熱做了實驗測試,分析了實驗結果,并進一步對其傳熱模型進行了理論研究,建立了一個計算分離器內壁面的平均傳熱系數的理論模型。該模型由四部分組成:氣相對流傳熱,顆粒非穩態導熱傳熱,顆粒輻射傳熱和煙氣三原子輻射傳熱。顆粒和壁面間的導熱傳熱由兩部分組成:顆粒—壁面的彈性碰撞接觸過程的傳熱和被壁面捕集的顆粒下落過程和壁面的接觸導熱傳熱。模型計算的平均傳熱系數可以與實驗數據吻合。但模型結果受壁面顆粒濃度和顆粒碰撞壁面的速度的影響較大,而目前這兩個參數還不能與進口速度和濃度相關聯。
 
關鍵詞: 冷卻型分離器; 傳熱模型

A theoretical wall-to-suspension heat transfer model for square-shaped cyclone separator

Yaxin Su1 Zhongyang Luo2 Kefa Cen2
( 1: College of Environmental Science and Engineering, Donghua University, Shanghai, 200051; 2: Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027 )

Abstract: Experimental test on the suspension-to-wall heat transfer in a water/stream-cooled square-shaped cyclone separator, which was developed for large compact CFB boilers was conducted and the results were analyzed. Based on the experiment, a theoretical study on the heat transfer model was carried out and a model to calculate the mean heat transfer coefficient was established. The heat transfer model of this paper consists 4 components: gas convection, particle unsteady heat conduction, particle radiation and flue-gas radiation. The particle unsteady heat conduction includes heat conduction during the particle-wall elastic impact and the transient heat conduction of the collected particles when they fall down along the wall surface. The surface-averaged heat transfer coefficient calculated by this model showed good agreement with the experimental data. Model results showed the particle concentration near the wall and the impact velocity of particle-to-wall had much effect on the heat transfer, while these two parameters can not be related to the inlet particle concentration and velocity.
Keywords: square-shaped cyclone separator; heat transfer model


⊙第86篇⊙

方形旋風分離器內氣固兩相流湍流特性的研究
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注意:本論文已在《熱能動力工程》2002,17(2):147-150發表
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蘇亞欣1 岑可法2 駱仲泱2
(1:東華大學環境科學與工程學院,上海,200051;2:浙江大學熱能工程研究所,杭州,310027)

摘 要: 應用三維顆粒動態分析儀(3D-PDA)對方形下排氣旋風分離器內氣固兩相流場進行了實驗研究。本文對流場、脈動速度、顆粒濃度、湍動能、湍流強度等的分布做了討論。方形旋風分離器內的流動具有Rankine渦的特點,即中心部分為強制渦區,邊壁附近是準自由渦區。邊角處因顆粒/壁面間的相互碰撞引起的準層流運動使得顆粒湍流脈動強烈,湍流動能和局部湍流強度在邊角附近取得較大值,表明在這里兩相流消耗了氣流的能量較多,是造成分離器壓力損失的主要區域之一。邊角有利于顆粒分離,主要原因是脈動強烈,消耗了顆粒和氣流的旋流運動的動能。研究結果為結構優化提供了基礎數據,并為今后的數值模擬研究提供了實驗對比。
 
關鍵詞: 方形下排氣分離器 氣固兩相湍流運動 三維顆粒動態分析儀(3D-PDA)

Experimental study on the turbulent characteristics of the gas-solid suspension in a square cyclone separator

Yaxin Su1 Kefa Cen2 Zhongyang Luo2
( 1: College of Environmental Science and Engineering, Donghua University, Shanghai, 200051; 2: Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027 )

Abstract:Three-dimensional Particle Dynamics Analyzer was employed to study the gas-solid flow in a square-shaped cyclone separator which was designed for large CFB application. Distribution of flow vector, fluctuating velocity, turbulent kinetic energy ,turbulent intensity and particle concentration were discussed. The swirling flow inside the cyclone showed the Rankine vortex characteristics, i e, strong swirling vortex at the central region of the cross-section and weak swirling quasi-free vortex near the wall. The quasi-laminar motion of particles at the corners due to particle-particle/wall collision enhanced the turbulent movement there, which led to the local peak value of the turbulent kinetic energy and turbulent intensity. The corner is one of the major region to cause pressure drop because the suspension at the corners consumed more energy of the flow. The corners were found to be beneficial to particle separation mainly because the strong fluctuating flow consumed much of the kinetic energy of both the particle and gas.
Keywords: square-shaped cyclone separator; heat transfer model


⊙第87篇⊙

方形旋風分離器內顆粒分布特性的實驗研究
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注意:本論文已在《燃燒科學與技術》2002,8(3):199-201發表
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蘇亞欣1 駱仲泱2 岑可法2
(1:東華大學環境科學與工程學院,上海,200051;2:浙江大學熱能工程研究所,杭州,310027)

摘 要: 應用三維顆粒動態分析儀(3D-PDA)對方形旋風分離器內的兩相流場進行了測試,得到了顆粒濃度和粒徑的分布,在進口高度的截面上,正對著分離器進口的右前角處顆粒的粒徑明顯大于其他地方的顆粒。在分離器中部的截面上,顆粒粒徑分布差別不大,但是在分離器的左前角附近顆粒濃度稍微高一些,而在右前角附近的顆粒濃度較低。顆粒濃度分布的差別和脈動速度的分布正好相反。
 
關鍵詞: 方形旋風分離器;顆粒分布;3D-PDA測試

Experimental Study on the Particle Distribution in a Square Cyclone Separator

SU Yaxin1 LUO Zhongyang2 CEN Kefa2
( 1: College of Environmental Science and Engineering, Donghua University, Shanghai, 200051; 2: Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027 )

Abstract:A 3 dimensional particle dynamic analyzer (3D-PDA) was employed to measure the gas-solid suspension flow in a lab-scale square cyclone separator with both downward exhaust exit and solid discharge. The particle concentration and diameter distribution at 2 sections were presented in this paper. At the upper part, e.g., at the section that is half of the inlet height from the separator top, the particle diameter at the front-right corner facing the inlet was found oberviusly larger than those at any other position. The particle diameter showed little difference at the section at the mid-height of the separator, while the particle concentration showed a little higher at the left-front corner and a little lower at the right-front corner. The particle concentration distribution was against particle fluctuating velocity.
Keywords: square cyclone; separator particle distribution; 3D-PDA measurement


⊙第88篇⊙

Proton beam fabrication of nickel stamps for nanoimprint lithography
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注意:本論文已在Nuclear Instruments and Methods in Physics Research B 231 (2005) 407–412發表
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K. Ansari , P.G. Shao(邵培革), J.A. van Kan, A.A. Bettiol, F. Watt
Physics Department, National University of Singapore, Lower Kent Ridge Road, Singapore 117542, Singapore

Abstract:Nickel stamps with micro and nano-scale relief features on their surfaces have been fabricated using proton beam writing coupled with nickel sulfamate electroplating. A focused beam of sub-micron 2.0 MeV protons was used to direct-write 3D patterns into spin coated PMMA resist, and a single step nickel sulfamate plating process has been used to produce metallic negatives from these patterns. The fabricated metallic stamps exhibit high aspect ratio surface patterns with smooth and vertical side-walls. Nano-indentation and atomic force microscopy (AFM) measurements of the features on the surface of the stamps indicate a hardness and side-wall roughness of 5 GPa and 7 nm respectively. Using nanoimprint lithography, the stamps fabricated using proton beam writing and electroplating have been successfully used to replicate patterns into PMMA.
Keywords: Nanoimprint lithography; Proton beam writing; Stamps; Electroplating; High aspect ratio


⊙第89篇⊙

Fabrication of a free standing resolution standard for focusing MeV ion beams to sub 30 nm dimensions
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注意:本論文已在Nuclear Instruments and Methods in Physics Research B 231 (2005) 170–175發表
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J.A. van Kan a,*, P.G. Shao(邵培革) a, P. Molter b, M. Saumer b, A.A. Bettiol a,
T. Osipowicz a, F. Watt a
a Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Dr 3,
Lower Kent Ridge Road, Singapore 117542, Singapore
b University of Applied Sciences Kaiserslautern, Location Zweibru¨ cken, Department Microsystems Technology,
Amerikastrasse 1, D-66482 Zweibru¨ cken, Germany

Abstract:With recent advances in nuclear microscopy, proton beam writing and the recent development of MeV ion nano probe facilities it is becoming increasingly important to have resolution standards with a high degree of side wall verticality. We present here a way of producing a high quality free standing resolution standards which can be used for high beam current applications like Rutherford Backscattering Spectrometry (RBS), particle induced X-ray emissions (PIXE), and low beam current applications such as secondary electron emission, scanning transmission ion icroscopy (STIM) and ion beam induced current (IBIC). These standards allow rapid focusing of MeV ion beams for high resolution nuclear microscopy applications as well as proton beam writing, where knowledge of the exact beam size is vital to guarantee reproducibility in writing nanostructures. This new standard has been used to measure a one-dimensional beam pro?le with 1 MeV protons and gave a FWHM of 29.2 nm which is the smallest value reported for MeV protons in STIM mode.
Keywords: Proton beam writing; Direct write; Nuclear microscopy; Resolution standard


⊙第90篇⊙

脈沖工藝在薄膜制備中的應用
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注意:本論文已在《真空科學與技術學報》,2004,24(增):33-37發表
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(EI已經收錄本文)
趙彥輝 林國強 董闖 聞立時
大連理工大學三束材料改性國家重點實驗室 遼寧 大連 116024

摘 要 本文綜述了國內外脈沖工藝在電弧離子鍍和磁控濺射中的應用。脈沖工藝為電弧離子鍍凈化大顆粒、增強膜基結合力、改善組織形貌、降低沉積溫度等起到了重要作用。電弧或濺射離子鍍高的離化率為脈沖工藝提供了最好的應用條件。最后,對脈沖工藝在薄膜制備中的應用前景進行了展望。
關鍵詞 電弧離子鍍 脈沖工藝 低溫沉積


ABSTRACT The application of pulse technique on arc ion plating and magnetron sputtering is summarized in the article. Pulse technique plays an important role in providing reduced marcroparticles pollution, enhancing adhesion between film and substrate, improving surface morphology and decreasing deposition temperature. Arc ion plating or magnetron sputtering provides the best application condition for pulse technique. Finally, prospect is given to the application foreground of pulse technique in film deposition.
KEY WORDS arc ion plating, pulse technique, low temperature deposition


⊙第91篇⊙

脈沖偏壓對電弧離子鍍Ti/TiN納米多層薄膜顯微硬度的影響
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注意:本論文已在《金屬學報》,2005,41(10):1106-1110發表
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趙彥輝1),林國強1, 2),李曉娜1, 2),董闖1),聞立時1, 3)
1) 大連理工大學三束材料改性國家重點實驗室,大連,116024
2) 大連理工大學物理系,大連,116024
3) 中國科學院金屬研究所,沈陽,110016

摘 要 用脈沖偏壓電弧離子鍍方法在高速鋼基體上沉積Ti/TiN納米多層薄膜,用正交實驗法設計脈沖偏壓電參數,考察脈沖偏壓對Ti/TiN納米多層薄膜顯微硬度的影響。結果表明,在所有偏壓參數(脈沖偏壓幅值、占空比和頻率)和幾何參數(調制周期和周期比)中,脈沖偏壓幅值是影響顯微硬度的最主要因素;當沉積工藝中脈沖偏壓幅值為900V、占空比為50%及頻率為30 kHz時,薄膜硬度可高達34.1GPa,此時多層膜調制周期為84nm,TiN、Ti單元層厚度分別為71nm和13nm;由于薄膜中的單層厚度較厚,納米尺寸的強化效應并未充分體現于薄膜硬度的貢獻中,硬度的提高主要與脈沖偏壓工藝,尤其是脈沖偏壓幅值對薄膜組織的改善有關。
關鍵詞:脈沖偏壓,電弧離子鍍,Ti/TiN納米多層薄膜,顯微硬度


EFFECT OF PULSED BIAS ON MICROHARDNESS OF TI/TIN MULTILAYER FILMS DEPOSITED BY ARC ION PLATING

ZHAO Yanhui 1), LIN Guoqiang 1, 2) , LI Xiaona 1, 2) , DONG Chuang 1) ,WEN Lishi 1, 3)
1) State Key Laboratory for Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116024
2) Physics Department, Dalian University of Technology, Dalian 116024
3) Institute of Metals Research, The Chinese Academy of Sciences, Shenyang 110016
Correspondent: LIN Guoqiang, professor, Tel: (0411)84708380-8301, Email: [email protected]
Supported by National High Technical Research and Development of Programme of China (2002AA302507)

ABSTRACT Ti/TiN nano-multilayer films were deposited on high-speed-steel (HSS) substrates using arc ion plating, in which orthogonal experiments were used to analyze the effects of the electrical parameters of pulsed bias on microhardness of Ti/TiN multilayer films. The results show that of all the pulsed bias related parameters including pulsed bias magnitude, duty ratio and frequency and the geometry parameters including modulation period and period ratio, pulsed bias magnitude is the major factor affecting microhardness of the multilayer films. The maximum microhardness of 34.1GPa was obtained with pulsed bias magnitude 900V, duty ratio 50% and frequency 30kHz, and the responding modulation period is 84nm, the unit set layer thickness of TiN and Ti are 71nm and 13nm, respectively. Due to the large unit set layer thickness used in the present experiments, the nano-scale strengthening effect is not obviously manifested. The increasing of the microhardness correlates in a significant manner with refining film microstructure resulted from the pulsed bias parameters especially the pulsed bias magnitude.
KEYWORDS pulsed bias, arc ion plating, Ti/TiN nano-multilayer films, microhardness


⊙第92篇⊙

混凝土自錨式懸索橋的設計與力學性能分析
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注意:本論文已在《大連理工大學學報,》2003,43(2):202-206發表
使用者請注明論文出處
EI已經收錄本文)
石磊 張哲 劉春城 檀永剛
(大連理工大學橋梁研究所,大連,遼寧,116024)

摘要:大連市金石灘懸索橋全長198m,主橋是24m+60m+24m的自錨式混凝土懸索橋,為中國首座此種類型的橋梁。本文對其結構形式作了介紹。通過計算實例,可以得出彈性理論適合于中小跨度的自錨式懸索橋的設計和計算。不計主梁軸力,結構的其余內力與地錨式懸索橋的差別不是很大,差值在10%以內。拱度和混凝土的收縮、徐變的影響比較明顯。與相應的水平加勁梁和不考慮收縮、徐變影響的計算結果比較,差值均在20%以上。分析所得結論對于同類橋梁的設計和研究具有一定的參考價值。
關鍵詞:混凝土 懸索橋 力學性能 自錨式


THE DESIGN AND MECHANICAL PERFORMANCE ANALYSES OF THE CONCRETE SELF-ANCHORED SUSPENSION BRIDGE

ZHANG Zhe SHI Lei LIU Chun-cheng TAN Yong-gang
(Bridge Institute of Dalian University of Technologe, Liaoning ,Dalian,116024,China)


Abstract: Jinshitan Bridge is the first self-anchored suspension bridge in China. Its total length is 198m,and the length of main span is(24+60+24)m. Some beneficial exploration and research is presented about the structure form 、design theory and internal force characteristics of the Jinshitan Bridge in this paper. Through computing the examples,the variational law of concrete self-anchored suspension bridge’s internal force is analyzed when the camber and the rise-span ratio are changed . And the law of the internal force affected by creep is also analyzed. Some conclusion can be consulted for designing and researching of this type of bridge.
Key words: concrete,suspension bridges,mechanical performance,self-anchored


⊙第93篇⊙

大跨懸索橋非線性隨機靜力分析
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注意:本論文已在《大連理工大學學報,》2004,44(3):421-424發表
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EI已經收錄本文)
石磊 ,劉春城,張哲,杜蓬娟
(大連理工大學橋梁研究所, 遼寧大連,116024)

摘要:大跨度懸索橋結構具有顯著的幾何非線性行為,且存在材料特性、幾何尺寸的隨機性。先對纜索采用較小抗彎剛度參數的梁單元,對懸索橋進行確定性的幾何非線性分析,然后采用響應面法進行非線性隨機靜力分析;最后針對一座大跨懸索橋,計算了在豎向活載作用下材料、幾何尺寸的隨機性對主梁跨中位移的影響。結果表明,結構隨機性的影響十分明顯。
關鍵詞: 懸索橋 響應面法 幾何非線性 隨機性
中圖分類號:U448.27 文獻標識碼:A


Nonlinear stochastic static analysis of long span suspension bridge

SHI Lei LIU Chun-Cheng ZHANG Zhe DU Peng-Juan
(Department of civil engineering, Dalian university of technology ,Dalian 116024)


Abstract: Geometrical nonlinear behaviors are very significant in long span suspension bridges, and the uncertainties of material, physical dimension etc greatly influence the structural response of suspension bridge. Beam element with small EI is used for the certain analysis of suspension bridge. Based on the Response Surface approach, the non-linearity of suspension bridge is researched in this paper. Finally, the mid-span deflection of a long span suspension bridge under vertical live load is analyzed when the elastic module of cable and hangers are assumed to be random correlated variables. Numerical results show that the randomness has a significant effect on the mid-span deflection.
Key words: Suspension bridge; Response Surface approach; Geometric non-linearity; Random


⊙第94篇⊙

自錨式懸索橋的發展綜述
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注意:本論文已在《世界橋梁》2003,1:5-9發表
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張哲,竇鵬,石磊,劉春城
(大連理工大學橋梁研究所, 遼寧大連,116024)

摘要:介紹自錨式懸索橋的特點和在國內外的發展情況,重點介紹我國在鋼筋混凝土自錨式懸索橋方面進行的設計與研究工作,并結合國內工程實際評價了該種橋型,采用鋼筋混凝土材料的優缺點及其發展空間。
關鍵詞: 懸索橋;自錨體系;綜述;實例


⊙第95篇⊙

Experimental Verification of the Physical Model for Droplet-Particles Cleaning in Pulsed Bias Arc Ion Plating
下載英語論文全文請點擊上面的鏈接

J. Mater. Sci. Technol. 2005,21(3):423-426

Yanhui ZHAO 趙彥輝1)+ , Guoqiang LIN1), Lishi WEN1, 2) and Chuang DONG1)
1)State Key Laboratory for Materials Modification by Laser, Ion and Electron beams, Dalian University of Technology, Dalian 116024, China
2)Institute of Metals Research, Chinese Academy of Sciences, Shenyang 110016, China

Abstract:It has been reported that application of pulsed biases in arc ion plating could effectively eliminate droplet particles. The present paper aims at experimental verification of a physical model proposed previously by us which is based on particle charging and repulsion in the pulsed plasma sheath. An orthogonal experiment was designed for this purpose, using the electrical parameters of the pulsed bias for the deposition of TiN films on stainless steel substrates. The effect of these parameters on the amount and the size distribution of the particles were analyzed, and the results provided sufficient evidence for the physical model.
KEY WORDS: Arc ion plating, Pulsed bias, TiN film, Droplet-particles


⊙第96篇⊙

基于NURBS的自由曲面精確擬合方法研究
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注意:本論文已在《機械工程學報》(中文版),2004,40(3):10-14發表
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孫玉文 吳宏基 劉 健
(大連理工大學機械工程學院 大連 116024)

摘要:提出了一類卷曲模型的NURBS曲面建模新方法。借助提出的截面輪廓設計技術,構造了點云數據的系列截面輪廓線,并以蒙皮操作為基礎得到了能反映點云基本幾何特征的基面。運用參數校正技術,給出了一種合理且比較有效的基面參數化方法,并由此用加權最小二乘算法實現了基于迭代的NURBS曲面的精確擬合。實際的算例結果驗證了方法的實用性及精確性,非常適于模具型腔建模。
關鍵詞:曲面擬合 非均勻有理B樣條 蒙皮 CAD/CAM

RESEARCH ON THE METHOD OF ACCURATE NURBS SURFACE FITTING TO SCATTERED POINTS
Sun Yu-Wen Wu Hong-Ji Liu Jian
( Dalian University of Technology)

Abstract:A NURBS surface fitting method with tight tolerance for wrap-around models is presented. Using the sectional design technique, two primary boundaries and some interior sectional curves are extracted. Then a base surface is constructed by skinning these curves. By means of the method of base surface parameterization, an accurate and smooth fitting surface is finally implemented. The practical example demonstrated the feasibility of the proposed method.
Key words: Surface fitting Non-uniform rational B-spline Skinning CAD/CAM


⊙第97篇⊙

離散算子差分法的單元函數
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注意:本論文已在《應用數學和力學》,2002,23(6):551-557發表
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田中旭1 唐立民2 劉正興1
(1. 上海交通大學,工程力學系,200030;2. 大連理工大學,工程力學系,116024)

摘要:本文給出了彈性力學離散算子差分法的離散格式,并給出了該方法的幾個板彎曲單元和平面四邊形單元,通過對它們的考察,分析了離散算子差分方法中的離散格式對單元位移函數的反映能力。在離散算子差分方法中,無論單元位移函數是否協調,其位移函數均能在離散格式中得到十分好再現,說明了離散算子差分方法的離散格式是一種性能很優良的離散格式。
關鍵詞:離散算子差分法;單元函數;準確再現

Element Functions of Discrete Operator Difference Method

Tian Zhongxu1 Tang Limin2 Liu Zhengxing1
1. Dept. of Eng. Mechanics, Shanghai Jiaotong Univ., Shanghai 200030, China
2.Dept. of Eng. Mechanics, Dalian Univ. Of Technology, Dalian 116024, China

Abstract: the discrete scheme called discrete operator difference for differential equations is given in this paper. Several difference elements for plate bending problems and plane problems are given. by investigating which, the ability of the discrete forms expressing to the element functions is talked about. In discrete operator difference method, the displacements of the elements can be reproduced exactly in the discrete forms whether the displacements are conforming or not. According to this point, discrete operator difference method is a method with good performance.
Key words: discrete operator difference method;element function; reproduce exactly


⊙第98篇⊙

基于遺傳算法的產品人機CAD研究
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注意:本論文已在《計算機工程與應用》2003,39(33):35-37,105發表
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劉肖健 李桂琴 景韶宇 陸長德
(西北工業大學工業設計研究所 西安友誼西路127號559信箱 710072)
梁艷霞
(徐州師范大學工業設計系 江蘇徐州 221000)

摘 要:將產品形態的人機設計問題從概念設計到詳細設計分為交互模式設計、關聯形態設計和獨立形態設計三個緊密聯系的層。應用進化設計和遺傳算法的基本原理,針對不同層次人機設計問題的特點分別進行具體研究,制訂了相應的解決策略,分析了其編碼方案與適應度函數的構造方式。最后構建了基于設計/制造一體化的人機進化設計過程原型系統。
關鍵詞:產品設計 人機工程學 遺傳算法 CAD


Product Ergonomics CAD Based on Genetic Algorithms
Liu Xiaojian Li Guiqin Lu Changde
Industrial Design Institute, Northwestern Polytechnical University
Liang Yanxia
Industrial Design Institute,Xuzhou Teacher’s University, Xuzhou, Jiangsu

Abstract: In this paper, product’s ergonomical design process was broken down to three periods: interactivity design, dimension design and individual form design. Based on Evolutionary design theory and genetic algorithms, ergonomical design problems were studied respectively for each period with encoding techniques and fitness function construction. And the proto system of the design process based on Design-Manufacture integrity system was also introduced.
Keywords: product design, ergonomics, genetic algorithms, CAD


⊙第99篇⊙

產品復雜曲面人機工程學設計研究
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注意:本論文已在《計算機應用與研究》2004,21(12):36-38發表
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劉肖健 余隋懷 陸長德
(710072 西北工業大學工業設計系)

摘 要:對產品形態設計中復雜曲面的人機工程學性能的設計問題進行了分析,研究了產品曲面人機性能設計的解決方案,應用遺傳算法工具實現了對復雜曲面形態解方案的隨機搜索以及通過程序進行自動評價與選擇的機制,建立了基于Unigraphics造型平臺的曲面人機設計過程機制與原型系統。
關鍵詞:產品設計 人機工程學 CAD 曲面 中圖分類號:TP391.72

A Study on the Ergonomics CAD of Complex Surface Design in Products

Liu Xiaojian Yu Suihuai Lu Changde
(Northwestern Polytechnical University)

Abstract: The Ergonomics design methods of complex surface design in products were analyzed in this paper. Genetic Algorithms were used to search solutions to complex surface and automatically evaluate and select the solutions. The proto-system was established on the Unigraphics platform.
Keywords: product design, ergonomics, CAD, surface, genetic algorithms


⊙第100篇⊙

基于Solidworks的人機工程學CAD二次開發
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注意:本論文已在《 計算機工程與應用 》2004,40(25):104-106,119發表
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劉肖健[1] 梁艷霞[2] 陸長德[1]
[1]西北工業大學工業設計系,西安710072
[2]徐州師范大學工業設計系,江蘇徐州221000

摘 要:對產品形態設計中復雜曲面的人機工程學性能的設計問題進行了分析,研究了產品曲面人機性能設計的解決方案,應用遺傳算法工具實現了對復雜曲面形態解方案的隨機搜索以及通過程序進行自動評價與選擇的機制,建立了基于Unigraphics造型平臺的曲面人機設計過程機制與原型系統。
關鍵詞:產品設計 人機工程學 CAD 曲面 中圖分類號:TP391.72

A Study on the Ergonomics CAD of Complex Surface Design in Products

Liu Xiaojian Yu Suihuai Lu Changde
(Northwestern Polytechnical University)

Abstract: The Ergonomics design methods of complex surface design in products were analyzed in this paper. Genetic Algorithms were used to search solutions to complex surface and automatically evaluate and select the solutions. The proto-system was established on the Unigraphics platform.
Keywords: product design, ergonomics, CAD, surface, genetic algorithms


 

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