力学十年:现状与展望

结合国家自然科学基金数理科学``十三五'规划战略研究报告以及学科发展态势评估系列研究报告《力学十年:中国与世界》, 本文简要介绍了国家自然科学基金力学学科的资助情况,通过重点介绍2006---2015年中国力学学科论文数、被引频次和排名前1%论文数、论文引用率、被引频次、论文相对引文影响、排名前1%高被引论文产出率、国际合作与自主研究等情况,对力学学科的发展态势进行了分析,并对力学学科今后发展提出了意见和建议.      

国家自然科学基金力学学科发展现状和“十三五”发展战略

结合国家自然科学基金力学学科"十三五"发展战略,介绍了力学学科的特点与战略地位,明确了国家自然科学基金力学学科的资助范围和指导思想.并通过对力学学科2006—2015年面上项目、青年科学基金、重点项目以及截至2015年国家杰出青年科学基金和优秀青年科学基金的申请和资助情况的分析,总结了自然科学基金的资助现状及其推动力学学科发展的作用.最后对"十三五"期间力学学科发展应该关注的问题给出了建议和政策措施.     

《力学学报》的产出及学术影响力分析

在钱学森先生领导下,于1957年创刊的《力学学报》作为力学学科历史最悠久的综合性期刊,她见证了20世纪50年代以来中国力学学科的发展轨迹,也见证了中国几代力学人才的成长和发展.本文采用文献计量指标,对《力学学报》从创刊至2018年的产出及学科影响力情况进行分析,用数据说明她对推动我国力学学科的发展、学术成果交流所做出的贡献.本文首先梳理了《力学学报》历年载文量、发文机构、发文作者等情况;然后分析了该刊在力学类期刊中的排名位置;最后,对载文内容特点进行分析,包括主要学科分布及近年刊文的研究热点.      

浅谈流体力学发展——从Batchelor百年诞辰纪念大会谈起

G.K. Batchelor是20世纪国际流体力学大师,在均匀湍流理论和低雷诺数微流体力学领域做出了开创性的贡献,他对流动追求物理和定量性理解的思想影响了近百年流体力学的发展,是流体力学顶级期刊Journal of Fluid Mechanics的创刊人,也是剑桥大学应用数学与理论物理系(DAMTP)的创建者,培养并影响了一大批在流体动力学理论、实验流体力学、湍流及稳定性、环境流体力学、多相流体力学、磁流体力学、微纳米尺度流体动力学等诸多领域建树卓越的学者.本文以G.K. Batchelor诞辰100周年纪念活动为契机,简要回顾了流体力学近300年的发展历程.概述了流体力学发展历经的以数学和物理为基础建立理论框架的经典流体力学、以应用需求为导向促使自身跨越发展的近代流体力学和以学科融合为特点外延丰富的现代流体力学三个重要阶段;以师承关系、代表性学者及其主要学术贡献为线索,总结了现代流体力学四大学派的形成及其近百年的传承沿革;以历史和发展的视角浅谈当代流体力学发展的动力和趋势,并以风沙环境力学为例,简述流体力学为分支学科发展提供的支撑和引领作用,分支学科的需求为流体力学内生发展提供驱动力...     

基于科学计量学的中国实验力学学科研究水平的国际化比较

本文采用科学计量学方法,对中国实验力学的研究水平进行评估。首先介绍科学计量学方法及评价指标,采用关键词及目标期刊构造相关文献集合;然后对中国实验力学学科的整体产出情况进行国际化比较,并根据中国实验力学学科发展特色,从光测力学、微纳米实验力学、专门化实验力学三个领域分析中国实验力学学科的产出优势及发展趋势,同时给出实验力学相关文献集合的学科分布以及5种重要期刊。结果表明,中国实验力学学科的研究论文产出能力位居全球第二,其影响力水平位居全球第五。     

环境力学与可持续发展

展望21世纪,环境问题是人类面临的最具有挑战性的课题,环境力学是力学学科新的生长点,本文概述了环境力学的历史沿革,还根据社会和经济可持续发展的需要和我国国情,提出了环境力学的研究方向与关键性基础研究问题,并以若干实例说明进行环境力学研究的途径．      

关于极端力学

随着前沿科学和新技术不断发展,工程材料与结构的超常规尺度、密度、硬度、刚度等性能以及在超常规温度、速度、场强和恶劣天气等极端服役环境中的力学响应规律,需要力学提供更为有效的理论和方法. 本报告从极端力学的基本定义和科学内涵出发,结合重大工程问题和大科学问题,从极端性能、极端载荷、学科发展等三个方面系统介绍了极端力学的研究现状,并总结了极端力学的特点及其对力学理论、计算方法和实验技术的挑战,最后对极端力学未来的发展进行了展望.      

2016年度力学科学处基金项目受理情况介绍

介绍了2016年度国家自然科学基金委员会数理科学部力学科学处受理的面上项目、青年科学基金项目、地区科学基金项目、重点项目、优秀青年科学基金、国家杰出青年科学基金和海外及港澳学者合作研究基金项目的申请情况.      

Closed trans-scale statistical microdamage mechanics

Damage and failure due to distributed microcracks or microvoids are on the challenging frontiers of solid mechanics. This appeals strongly to tools not yet fully developed in continuum damage mechanics, in particular to irreversible statistical thermodynamics and a unified macroscopic equations of mechanics and kinetic equations of microstructural transformations. This review provides the state of the art in statistical microdamage mechanics.

On non-objective citation to scientific publications on mechanics and control systems

The problem of non-objective citation to scientific publications on mechanics and control systems that arose with the advent of the global scientific information environment is discussed. Examples demonstrating the importance of this problem are presented. It is concluded that non-objective citation is not always due to the language barrier     

A 1-D theory for extensional deformation of a viscoelastic filament under exponential stretching

We consider a viscoelastic filament placed between two coaxial discs, with the bottom plate fixed and the top plate pulled at an exponential rate. Using a slender rod approximation, we derive a one-dimensional (1-D) model which describes the deformation of a viscoelastic filament governed by the Oldroyd-B constitutive model. It is assumed that the flow is axisymmetric and that inertia and gravity are negligible. One solution of the model equations corresponds to ideal uniaxial elongation. A linear stability analysis shows that this solution is unstable for a Newtonian fluid and for viscoelastic filaments with small Deborah number (De ≤ 0.5). For Deborah number greater than 0.5, ideal uniaxial elongation is linearly stable. Numerical solution of the nonlinear equations confirms the result of the linear stability analysis. For initial conditions close to ideal uniaxial flow, our results show that if De > 0.5, the central portion of the filament undergoes considerable strain hardening. As a result, the sample remains almost cylindrical and the deformation approaches pure uniaxial extension as the Hencky strain increases. For De ≤ 0.5, the Trouton ratio based on the effective extension rate at the mid-plane radius gives a much better approximation to the true extensional viscosity than that based on the imposed stretch rate.     

科学与工程中的应用力学

回顾1600年至1900年间力学、19世纪物理学和同时期的工程教育的发展史,描述了应用力学的发展及其与科学和工程的关系．随之讨论现代物理学、现代工程学和作为科学与工程的一门学科的应用力学的形成,后者被《AppliedMechanicsReviews》杂志分为94个学科方向共10个门类．总结了科学与工程之间的关系以及应用力学与其它学科的相互影响．     

Trends in complexity theories and computation in the social sciences

A modified bibliometric study and citation analysis of the use of complexity theories, encompassing chaos and complexity theory, and computational simulation in published literature was conducted. Articles published during 1971-1999 in four disciplines were examined: business, education, psychology and sociology. Overall, there was a marked pattern of increased use in the terms within the social sciences. There was a differentiated use of the terms between disciplines. A qualitative study on a subset from each discipline was generated to create a disciplinary profile of the quantitative and qualitative use of the terms in research activities, called a problem topology. Three research implications that arise from the differential adaptation of the theories and methods into the four social sciences are discussed.     

The use of images in fluid mechanics

Still images, photographs and drawings, as well as movies are widely used in fluid mechanics and this has been true since the very early developments of this discipline. The intrinsic geometrical complexity of fluid flows, in particular when they are turbulent, explains this necessity of using visual representations to gain a physical understanding of the phenomena involved. The aesthetic appeal of images in fluid mechanics research is another reason why their use is more prevalent than in other fields of the physical sciences.     

Extreme mechanics

With the development of cutting-edge sciences and new technologies, we have to consider the size, the density, the hardness, the stiffness and other properties of engineering materials and structures beyond the conventional ranges, as well as their mechanical behavior in extreme environments, such as ultra-conventional temperature, speed, physical and chemical fields, and severe weather, and more effective theories and methods of mechanics are required. This paper first gives the fundamental definition and the scientific connotation of extreme mechanics, then reviews the studies of extreme mechanics from three aspects: the extreme properties, the extreme loads, and the discipline development, as well as major engineering and scientific challenges. The characteristics of extreme mechanics and major challenges in the aspects of mechanical theory,computational methods and experimental techniques are discussed. Prospectivei developments of extreme mechanics are suggested.     

Evaluation of inverse Fourier transforms through romberg integration

This study deals with evaluation of inverse integral transforms through numerical integration. Arguments are presented to explain that such a numerical evaluation is mathematically incorrect. In recent years, a sudden increase has been noticed in the number of research publications in which Romberg integration is said to have used in evaluating the inverse Fourier transforms. In this regard, even the references cited in these papers do not support such an evaluation but suggest contrary. An immediate concern is to caution the researchers studying the source problems in the field of solid mechanics over the use and approval of an erroneous numerical technique.     

土塑性力学的建立与发展

土塑性力学是现代塑性理论在土力学中应用的一门新兴学科.本文回顾了近30年来土塑性力学的形成和发展,并介绍了它的主要内容.      

CFD based mini- vs. micro-system delineation in elongated bubble flow regime

Delineation of mini- and micro-scale channels with respect to two-phase flow has been the subject of many research papers. There is no consensus on when the small channel can be characterized as a mini-channel or micro-channel. The idea proposed by this paper is to use the normalized bubble nose radius, liquid film thickness top over bottom ratio, and bubble shape contour, which are found under normal gravity conditions in slug flow through a horizontal adiabatic channel, as the delineation criteria. The input parameters are bubble nose radius and bubble nose velocity as the characteristic length scale and characteristic velocity scale respectively. 3D numerical simulation with ANSYS FLUENT was used to obtain the necessary data. Following CFD practice, a mesh independence study and a numerical model validation against published experimental data were both conducted. Analysis of the numerical simulation results showed that channels with D ⩽ 100 μm can be characterized as a micro-system, while channels with D ⩾ 400 μm belong to mini-systems. The region 200 μm ⩽ D ⩽ 300 μm represents a transition from the micro-scale to mini-scale.     

高瞻远瞩加强力学基础研究

本文简要回顾了力学学科的性质与作用;近代力学的发展与现状;我国力学研究的概况;对发展力学学科提出了若干建议。      

结构动力学与运载火箭技术发展

力学作为工程研究的基础学科,在运载火箭的设计中起着至关重要的作用.结构动力学作为分支学科之一在其中扮演着重要角色,其发展水平很大程度上可反映火箭总体设计能力.本文着眼于结构动力学与运载火箭技术的结合点,简述其发展过程,并对其进一步发展方向提出设想.