新材料力学研究进展学术研讨会会议纪要

由中国力学学会主办,哈尔滨工业大学、清华大学和实验力学专业委员会承办的"新材料力学研究进展"学术研讨会于2010年2月3至6日在黑龙江省哈尔滨市召开.本次研讨会由来自北京大学、哈尔滨工业大学、天津大学、国防科学技术大学、清华大学、西安交通大学和中国科学院力学研究所等16家科研院所的40余名教授、专家和学者进行了广泛的交流.大会开幕式由清华大学谢惠民教授主持,中国力学学会副理事长、北京大学方岱宁教授致开幕辞.     

胡乾善简介

胡乾善出生于1911年4月,河南省通许县人.九岁随其父到北京居住.1929年在北京师大附中高中毕业后考入清华大学物理系.当时一些学识渊博、知名的物理学家如吴有训、周培源、萨本栋等教授都在该校执教.1933年他在清华大学物理系毕业后留校作研究生,次年考取河南省官费留英,于当年秋进入英国     

延请名师 分享精品——一次理论力学教学实践浅析

为提高理论力学的教学效果,开阔学生视野,分享清华大学的国家精品课建设成果,聘请清华大学李俊峰教授来我校讲授土木07级的理论力学课.本文针对学生的课上听课情况、课下复习和作业情况进行了调查.在总结调查结果的基础上,重点针对改革力度比较大的静力学部分教学,进行了初步分析.     

胡乾善简介

胡乾善出生于1911年4月,河南省通许县人.九岁随其父到北京居住.1929年在北京师大附中高中毕业后考入清华大学物理系.当时一些学识渊博、知名的物理学家如吴有训、周培源、萨本栋等教授都在该校执教.1933年他在清华大学物理系毕业后留校作研究生,次年考取河南省官费留英,于当年秋进入英国 ...     

分享精品—————— 一次理论力学教学实践浅析

 为提高理论力学的教学效果,开阔学生视野,分享清华大学的国家精品课建设成果, 聘请清华大学李俊峰教授来我校讲授土木07级的理论力学课. 本文针对学生的课上听课情 况、课下复习和作业情况进行了调查. 在总结调查结果的基础上,重点针对改革力度比较大 的静力学部分教学,进行了初步分析.     

第四届国际雷诺平均-大涡模拟混合方法学术会议纪要

由清华大学、中国力学学会、德国宇航院和欧盟第七框架协议ATAAC项目联合主办,清华大学承办的“第四届国际雷诺平均{大涡模拟混合方法学术会议”(The 4th Symposiumon RANSLES Hybrid Methods)于2011年9月28~30日在北京凯迪克-格兰云天大酒店召开.瑞典国防研究院(FOI)彭夏辉(Shia-Hui Peng)教授为大会组委会主席、欧洲航空防务与空天公司(EADS)资深专家WernerHaase博士、德国宇航院(DLR)ATAAC项目负责人Dieter Schwamborn博士担任大会组委会的共同主席,清华大学航天航空学院符松教授担任本届大会主席;大会会务组织由中国力学学会办公室承担,清华大学航天航空学院先进湍流模拟研究室(LAST)相关教师、博士后和研究生负责接待、会务、会场和翻译等工作.      

第三届"二十一世纪的实验力学学科发展-海峡两岸实验力学研讨会"会议纪要

由中国力学学会实验力学专业委员会主办,内蒙古工业大学协办的第三届"二十一世纪的实验力学学科发展-海峡两岸实验力学研讨会"于2009年7月28日在内蒙古呼和浩特举行.本次研讨会由来自清华大学(北京)、天津大学、中科院力学所等大陆10所院校和科研单位的15名一线学者、教授等高层次青年科学家和工程专家,与来自台湾清华大学、成功大学等10所院校和科研单位的16名学者进行了广泛地交流.大会由内蒙古工业大学邢永明教授主持开幕式,天津大学亢一澜教授、清华大学(新竹)王伟中教授分别致辞.     

科研教学双丰收

科研教学双丰收符松清华大学工程力学系,北京１０００８４清华大学工程力学系近几年来在科研与教学等各项工作上继续取得优异成绩．１９９６年我系发表的学术论文首次突破４００篇,达到４６７篇,居清华大学之首．其中１２７篇发表于国外学术刊物．１９９５年度（９６年...      

清华大学破坏力学教育部重点实验室研究工作进展(2005-2008年)

国家教委于1993年12月批准成立破坏力学开放研究实验室(failure mechanics laboratory, FML),挂靠在清华大学工程力学系,1999年正式命名为破坏力学教育部重点实验室.自1994年以来,在教育部和清华大学的领导与支持下,作为重点学科固体力学中的骨干研究基地,FML在科研上承担了众多国家重点科技攻关项目、"973"和"863"项目以及国家自然科学基金重大、重点和面上项目,取得了多项国家和部委级的科技成果奖和人才奖,在科研和人才两方面取得了显著的成绩.     

小问题

346.图1所示系统中,均质杆OA长l重W,物体E重P,l1=3/2l.不计轴承处摩擦及绳的重量,求系统平衡时的θ角. (贾书惠,清华大学工程力学系)     

Patterns,fabric, anisotropy,and soil elasto-plasticity

This paper proposes a new method in the theory of soil plasticity – an advance on Hill [The Mathematical Theory of Plasticity, Clarendon Press, Oxford]. The method assumes that soil fabric consists of inter-locking, inter-twining, inter-laced, juxtaposed, and superposed elementary units called “patterns”. A mechanics of patterns is developed. As well as elastic and plastic components, a third strain-increment component is deduced which helps explain non-associated flow. The proposed method leads to explanations of critical states, anisotropy, sensitivity, the Bauschinger effect, and swept-out memory. All these appear in the method as near-inescapable features of plastic solids. Results are illustrated in detail for plane strain biaxial processes.     

Diffusion models for innovation: s-curves, networks, power laws, catastrophes, and entropy

This article considers models for the diffusion of innovation would be most relevant to the dynamics of early 21st century technologies. The article presents an overview of diffusion models and examines the adoption S-curve, network theories, difference models, influence models, geographical models, a cusp catastrophe model, and self-organizing dynamics that emanate from principles of network configuration and principles of heat diffusion. The diffusion dynamics that are relevant to information technologies and energy-efficient technologies are compared. Finally, principles of nonlinear dynamics for innovation diffusion that could be used to rehabilitate the global economic situation are discussed.     

Steady,oblique, detonation waves

Normal and oblique, steady planar detonation waves have been theoretically and computationally examined using the Zeldovich, von Neumann, Döring model. Combustion is between a methane/hydrogen mixture and dry air assuming, first, complete combustion, then an equilibrium solution. Prescribed parameters are the upstream values for the pressure, temperature, and Mach number, the fuel/air equivalence ratio, a hydrogen/methane ratio, and the detonation wave angle. For a given upstream state, the angle varies from its normal wave value in increments of 10 ^o to non-integer wave angles that correspond to the Chapman-Jouguet state for complete combustion and for an equilibrium solution. For each solution, detailed results are provided for the upstream state, the state just downstream of the shock, and the two downstream states. Over 340 solutions in a report (Emanuel and Tuckness 2002) are provided, thereby establishing, for the first time, comprehensive tables that can be used to provide quick estimates, establish trends, and check CFD results. This paper describes the basis for the model, briefly outlines the analytical and numerical method, and discusses several insights.     

One-dimensional,time-dependent,homogeneous, two-phase flow in volcanic conduits

A one-dimensional, time-dependent, isothermal, homogeneous, two-phase flow model was developed to study magma ascent in volcanic conduits. The physical modeling equations were numerically solved by means of a TVD (total variation diminishing) predictor-corrector procedure and by means of a predictor-corrector technique based on the method of characteristics. The results from the transient model were verified with an analytical solution for wave propagation in conduits without friction and gravitational effects. The numerical solutions were also compared with those of a steady-state, homogeneous, two-phase model for basaltic and rhyolitic magma ascents in the fissures and circular conduits of Vesuvius and Mt St. Helens. An application of the model to magma decompression in conduits indicates very short times for gas exsolution, fragmentation, and shock wave propagation, implying that the modelling of gas exsolution should involve non-equilibrium kinetics effects. Future coupling of the transient magma ascent model with magma chamber and pyroclastic dispersion models should allow for more realistic simulations of the time-dependent behavior of real volcanic eruptions.     

Physiology,mechanics, and rheology

Biological systems possess rather specialized mechanical properties, acquired as part and parcel of the evolutionary development of the system as a whole. Their optimization permits the system to function physiologically in the context of a biologically essential, but mechanically often widely varying environment with adequate efficiency. The system's environment is its source of food and shelter; it represents the space in which it forages or preys on other creatures and in which it has to defend itself against still others. Thus, the system has to develop an adequately pliant, rheologically matched, energy-use efficient, mechanical interface between it and its surroundings. This must be an interface that both effectively excludes, but also effectively admits, the external. Internally, as well, it has to adapt the mechanical properties of cell and connective tissue to physiological function and the efficient performance of useful work. This will be illustrated by way of examples. Blood rheology is briefly discussed and put into the context of clinical hemorheology and epithelial protection; and function, by way of a mucus coating or a mucociliary clearance system, is reviewed in some detail. The importance of all aspects of rheological matching is demonstrated.Delivered as a Keynote Lecture at the Golden Jubilee Conference of the British Society of Rheology and Third European Rheology Conference, Edinburgh, 3–7 September, 1990.