结构动力分析中的逐级近似缩聚法

本文基于逐级逼近理论建立了一种动力模型缩聚的逐级近似减缩法。该方法具有协调和非协调格式。本文基于ＳＡＲＴ导出了一般的ｋ级递推减缩公式，其中一级近似和二级近似减缩式就是现有的Ｇｕｙａｎ／Ｉｒｏｎｓ减缩和ＩＲＳ减缩。算例表明，在物理型减缩技术方面，本文的三级近似减缩模型精度最好。     

结构分析集成化系统ISAS

系统ＩＳＡＳ的三个组成部分是：有限元网格自动生成模块ＭＥＳＨ，有限元分析模块ＦＥＡ和后处理图形生成模块ＰＰＧ，三个部分采用统一的数据结构，协调的模块接口，极少量人工干预及多种用户选择的人机界面．系统自动化程度高且使用方便．     

结构分析集成化系统ISAS

系统ＩＳＡＳ的三个组成部分是：有限元网格自动生成模块ＭＥＳＨ，有限元分析模块ＦＥＡ和后处理图形生成模块ＰＰＧ，三个部分采用统一的数据结构，协调的模块接口，极少量人工干扰及多种用户选择的人机界面，系统自动化程度高且使用方便。     

工业装备结构分析国家重点实验室研究工作介绍

工业装备结构分析国家重点实验室研究工作介绍顾元宪徐新生大连理工大学工业装备结构分析国家重点实验室，大连１１６０２４工业装备结构分析国家重点实验室，利用世界银行贷款建于大连理工大学，拥有ＣＲＡＹＳ／ＭＰ小巨型机和ＳＧＩ图形工作站等计算机系统，以及ＭＴＳ...     

THE ANALYTICAL STUDY ON THE LASER INDUCED REVERSE－PLUGGING EFFECT BY USING THE CLASSICAL ELASTIC PLATE THEORY（II）──REVERSE－BULGE MOTION

ＴＨＥＡＮＡＬＹＴＩＣＡＬＳＴＵＤＹＯＮＴＨＥＬＡＳＥＲＩＮＤＵＣＥＤＲＥＶＥＲＳＥ－ＰＬＵＧＧＩＮＧＥＦＦＥＣＴＢＹＵＳＩＮＧＴＨＥＣＬＡＳＳＩＣＡＬＥＬＡＳＴＩＣＰＬＡＴＥＴＨＥＯＲＹ（ＩＩ）──ＲＥＶＥＲＳＥ－ＢＵＬＧＥＭＯＴＩＯＮ￥(周益春，...     

THE BENDING OF THIN RECTANGULAR PLATES WITH MIXED SUPPORTED SEGMENTS OF STRAIGHT EDGES

ＴＨＥＢＥＮＤＩＮＧＯＦＴＨＩＮＲＥＣＴＡＮＧＵＬＡＲＰＬＡＴＥＳＷＩＴＨＭＩＸＥＤＳＵＰＰＯＲＴＥＤＳＥＧＭＥＮＴＳＯＦＳＴＲＡＩＧＨＴＥＤＧＥＳＣｈｅｎＬｉ－ｚｈｉ（陈立志）（ＱｉｎｈｕａｎｇｄａｏＰｏｒｔＡｕｉｈｏｒｉｔｙ，Ｑｉｎｈｕａｎｇｄａ...     

一种低成本民机组合导航系统研究

单陀螺捷联惯导系统（ＳＧＳＩＮＳ）不仅具有和经典捷联惯导系统相同的基本功能，而且有体积小、重量轻、成本低、可靠性高等优点。本文重点在于ＳＧＳＩＮＳ与大气数据系（ＡＤＳ）组合的研究。研究结果表明，如果使其与ＡＤＳ组合，可以满足中程民机导航的要求。     

THE ANALYTICAL STUDY ON THE LASER INDUCED REVERSE－PLUGGING EFFECT BY USING THE CLASSICAL EIASTIC PLATE THEORY（I）─TEMPERATURE FIELDS

ＴＨＥＡＮＡＬＹＴＩＣＡＬＳＴＵＤＹＯＮＴＨＥＬＡＳＥＲＩＮＤＵＣＥＤＲＥＶＥＲＳＥ－ＰＬＵＧＧＩＮＧＥＦＦＥＣＴＢＹＵＳＩＮＧＴＨＥＣＬＡＳＳＩＣＡＬＥＩＡＳＴＩＣＰＬＡＴＥＴＨＥＯＲＹ（Ｉ）─ＴＥＭＰＥＲＡＴＵＲＥＦＩＥＬＤＳＺｈｏｕＹｉｃｈｕｎ...     

THE ANALYTICAL STUDY ON THE LASER INDUCED REVERSE－PLUGGING EFFECT BY USING THE CLASSICAL ELASTIC PLATE THEORY（Ⅰ）－TEMPERATURE FIELDS

ＴＨＥＡＮＡＬＹＴＩＣＡＬＳＴＵＤＹＯＮＴＨＥＬＡＳＥＲＩＮＤＵＣＥＤＲＥＶＥＲＳＥ－ＰＬＵＧＧＩＮＧＥＦＦＥＣＴＢＹＵＳＩＮＧＴＨＥＣＬＡＳＳＩＣＡＬＥＬＡＳＴＩＣＰＬＡＴＥＴＨＥＯＲＹ（Ⅰ）－ＴＥＭＰＥＲＡＴＵＲＥＦＩＥＬＤＳＺｈｏｕＹｉｃｈｕｎ...     

THE LAGRANGE DYNAMIC EQUATIONS OF MULTI－RIGIDBODY SYSTEMS WITH EXTERNAL SHOCKS

ＴＨＥＬＡＧＲＡＮＧＥＤＹＮＡＭＩＣＥＱＵＡＴＩＯＮＳＯＦＭＵＬＴＩ－ＲＩＧＩＤＢＯＤＹＳＹＳＴＥＭＳＷＩＴＨＥＸＴＥＲＮＡＬＳＨＯＣＫＳ￥ＺｈａｎｇＤｉｎｇｇｕｏ（章定国）（ＮａｎｊｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏ...     

有效集法在数学规划加权残值法中的应用

本文研究有效集法在数学规划加权残值法求解微分方程问题中的应用。从理论上和实际应用方面 阐明，对于数学规划加权残值法和线性规划问题，有效集法比常用的单纯形法更简便、易程序化、计算速度更快，因此更适用于数学规划加权残值法求解微分方程问题。     

双柱单锥型液-液旋流管内流场的激光诊断

应用激光测速仪，对一种双柱单锥型液 液旋流管内的流动结构，进行了全场范围内的多工况流动诊断研究．揭示出其切向速度由内旋流区和外旋流区构成，其中内旋流区中的速度分布符合准强制涡关系，外旋流区中的速度分布符合准自由涡关系；轴向速度由上行流动区和下行流动区构成，两者之间在直管段以零速点作分界，在锥体段则以零速区作过渡并伴随有一定的回流出现，且该过渡区或回流区的大小随锥体截面的收缩而减小，直到进入直管段后消失；各湍流量的分布以管芯处最大向外逐渐减小，沿轴向是直管段中的湍流度大于锥体段中的湍流度，而且湍流度在旋流管内具有各向异性的特性．     

Coreflooding Studies to Evaluate the Impact of Salinity and Wettability on Oil Recovery Efficiency

In this work, coreflood studies were carried out to determine the recovery benefits of low salinity waterflood compared to high salinity waterflood and the role of wettability in any observed recovery benefit. Two sets of coreflood experiments were conducted; the first set examined the EOR potential of low salinity floods in tertiary oil recovery processes, while the second set of experiments examined the secondary oil recovery potential of low salinity floods. Changes in residual oil saturation with variation in wettability, brine salinity and temperature were monitored. All the coreflood tests gave consistent increase in produced oil, corresponding to reduction in residual oil saturation and increase in water-wetness (for the second set of experiments) with decrease in brine salinity and increase in brine temperature.     

爆炸对自然磁场干扰机理

爆炸产生的电磁场对爆炸测试有较明显的干扰, 一些含金属炸药产生的电磁干扰甚至可以使设备失效, 为了给出爆炸产生电磁效应的理论分析方法和特性, 针对常规炸药爆炸过程中观察到的自然磁场扰动现象进行理论机理和数值模拟研究. 采用热平衡电离理论描述爆炸过程中产生的电离气体, 结合爆炸问题的数值模拟方法, 获得爆炸场中电导率的时空分布, 计算磁场扩散率; 基于非理想全磁流体力学方程求解一定磁扩散率下等离子体高速运动引起的自然磁场扰动, 实现爆炸产生磁场效应的二维模拟; 对比炸药不同起爆条件对产生磁场扰动的影响, 结果表明: 炸药起爆参数对磁场扰动有很大的影响, 这种影响源自于电导率的巨大差异, 虽然爆轰产物的高速运动有引起磁场大幅度扰动的能力, 然而只有具有一定电导率的爆轰气体才能冻结磁场扰动. 数值模拟结果与文献中的结果进行了对比, 模拟得到的由电磁波引起的磁场扰动在时间尺度上与文献结果符合较好, 从一定程度上证明了数值模拟方法的可靠性. 本文的数值模拟结果指出炸药几何构型不对称的时候, 在自然磁场取不同方向时将会产生不同的磁场扰动强度, 而这是目前该领域中尚且无人关注和讨论过的问题.      

岩体结构面倾向参数概率分布函数改进的Bayes推断方法

三峡船闸是世界上最大的船闸。该地区断层及节理比较发育,且具有一定的随机统计性,它对岩体力学性质起重要的控制作用。为了研究节理倾向的概率分布特征,本文引入以Bayes 最小熵优度比较检验为基础的概率分布的改进Bayes 统计推断方法,基于三峡工程永久船闸节理岩体3373 条结构面的实测参数,就对岩体力学性质起控制作用的各组结构面的倾向参数的概率分布进行了研究。文章最后还讨论了推断的最优分布参数,估计了结构面参数的检验误差范围。     

Friction term discretization and limitation to preserve stability and conservation in the 1D shallow‐water model: Application to unsteady irrigation and river flow

Friction is one of the relevant forces included in the momentum equation of the 1D shallow‐water model. This work shows that a pointwise discretization of the friction term unbalances this term with the rest of the terms in the equation in steady state. On the other hand, an upwind discretization of the friction term ensures the correct discrete balance. Furthermore, a conservative technique based on the limitation of the friction value is proposed in order to avoid unbounded values of the friction term in unsteady cases of advancing front over dry and rough surfaces. This limitation improves the quality of unsteady solutions in wet/dry fronts and guarantees the numerical stability in cases with dominant friction terms. The proposed discretization is validated in some test cases with analytical solution or with measured data and used in some practical cases. Copyright © 2007 John Wiley & Sons, Ltd.     

连通容器泄爆过程的影响因素

以甲烷/空气混合物为研究对象，开展了连通容器气体泄爆影响因素的实验研究。结果表明:连通容器泄爆片泄爆时，随着破膜压力和量纲一泄压比的减小，大、小球容器的最大泄爆压力均增大；在等量纲一泄压比条件下，随着连接管道长度的增加，传爆容器的最大泄爆压力增大。连通容器无膜泄爆时，大球点火条件下，无论管长如何，起爆容器和传爆容器均比单个容器最大泄爆压力大。小球点火条件下，当管道长度为0.45 m时，起爆容器和传爆容器的最大泄爆压力均小于单个容器。连通容器无膜泄爆且量纲一泄压比相同时，当管道长度为0.45 m时，大、小容器内的最大泄爆压力基本相等；当管道长度为2.45 m时，大容器点火时，传爆容器最大爆炸压力大于起爆容器，但小容器点火时，起爆容器最大泄爆压力大于传爆容器；当管道长度为4.45和6.45 m时，传爆容器最大泄爆压力均大于起爆容器。     

延性动态损伤的细观描述

对动载荷下材料的延性动态损伤的细观力学研究现状进行了评述，详细讨论了现有的几类典型的动态延性损伤的微孔生长模型。针对目前该领域工作中存在的问题，指出了今后应开展的工作方向。     

Galerkin finite element simulation of convection driven by rotation and gravitation

The performance of the Galerkin finite element method when applied to time-dependent convection involving rotation, self-gravitation and the normal gravity field in a horizontal cylinder is discussed in this paper. The governing equations, the parameters of the problem and our implementation of the numerical schemes are presented. The accuracy, spatial scale of resolution, flexibility and robustness of the resulting code show the element method as a valuable tool for research in this area or in related problems in astrophysical fluid dynamics. The numerical difficulties in large-amplitude flows are associated with an error-control scheme for time integration and the ‘short-time’ wiggles in transient Dirichlet problems. Coarse grids give the correct qualitative picture in most simulations, but the type of solution at short time (and hence grid refinement) presumably resolves the degeneracy in the azimuthal orientation of convection cells in flows driven by self-gravitation and (perhaps) centrifugal buoyancy. The final state in transient flows is a motionless isothermal fluid. However, residual motions can be nullified only in the limit of zero grid size in flows driven by centrifugal buoyancy (self-gravitation), while a fairly coarse grid is sufficient for this purpose in normal gravity-driven flows.     

Flow patterns and heat transfer in vertical upward air–water flow with surfactant

Flow patterns, the pressure drag reduction and the heat transfer in a vertical upward air–water flow with the surfactant having negligible environmental impact were studied experimentally in a tube of 2.5 cm in diameter. Visual observations showed that gas bubbles in the air–water solution with surfactant are smaller in size but much larger in number than in pure air–water mixture, at the all flow regimes. The transition lines in the flow regime map for the solution of air–water mixture with surfactant of the 300 ppm concentration are mainly consistent with the experimental data obtained in clear air–water mixture. An additive of surfactant to two-phase flow reduces the total pressure drop and decrease heat transfer, especially in the churn flow regime.