This paper presents a review on some developments of numerical methods for linear and nonlinear fluid-solid interaction (FSI) problems with their applications in engineering. The discussion covers the four types of numerical methods: 1) mixed finite element (FE)-substructure-subdomain model to deal with linear FSI in a finite domain, such as sloshing, acoustic-structure interactions, pressure waves in fluids, earthquake responses of chemical vessels, dam-water couplings, etc.; 2) mixed FE-boundary element (BE) model to solve linear FSI with infinite domains, for example, VLFS subject to airplane landing impacts, ship dynamic response caused by cannon / missile fire impacts, etc.; 3) mixed FE-finite difference (FD) / volume (FV) model for nonlinear FSI problems with no separations between fluids and solids and breaking waves; 4) mixed FE-smooth particle (SP) method to simulate nonlinear FSI problems with f-s separations as well as breaking waves. The partitioned iteration approach is suggested in base of available fluid and solid codes to separately solve their governing equations in a time step, and then through reaching its convergence in coupling iteration to forward until the problem solved. The selected application examples include air-liquid-shell three phases interactions, LNG ship-water sloshing; acoustic analysis of air-building interaction system excited by human foot impacts; transient dynamic response of an airplane-VLFS-water interaction system excited by airplane landing impacts; turbulence flow-body interactions; structure dropping down on the water surface with breaking waves, etc. The numerical results are compared with the available experiment or numerical data to demonstrate the accuracy of the discussed approaches and their values for engineering applications. Based on FSI analysis, linear and nonlinear wave energy harvesting devices are listed to use the resonance in a linear system and the periodical solution in a nonlinear system, such as flutter, to effectively harvest wave energy. There are 231 references are given in the paper, which provides very useful resources for readers to further investigate their interesting approaches.

Insects are the earliest, most numerous and smallest fliers in the world. They can hover, fly forward, climb and descend with ease while demonstrating amazing stabilities, and they can also maneuver in impressive ways like no other organisms could. Although the wing of an insect beats at high frequency, the wing's relative velocity is small owing to the small wing length. As a result, the mean lift coefficient of wing required to balance the insect weight is relatively high, about 1.5–2, much higher than that of an airplane at cruising flight. The Reynolds number of insects' wings is small, ranging from about 10 to 3 500. How the required high-lift coefficient is produced at such low Reynolds number? Researchers are very interested in this question and in recent years, significant progress has been made in the area. Works before 2005 have been discussed in detail in several review papers, and in this article, we review the advances made since 2005. We begin with an overview of the flapping kinematics and basic equations of fluid dynamics. It is followed by a summary of the works before 2005. Then we review the advances made since 2005, dealing in turn with measurement of wing motion in freely-flying insects, leading-edge vortex, effect of wing deformation and corrugation, vortex wake of flapping wings, ground effect and aerodynamic interaction between wings and body, flight of tiny insects, flight of butterfly and dragonfly, and maneuvering flight. Finally, we make remarks on the state-of-the-art of this research field and speculate its outlooks in the near future.

Cancer is a leading cause of mortality worldwide causing human deaths.Circulating tumor cells(CTCs) are cells that have detached from a primary tumor and circulate in the bloodstream; they may constitute seeds for subsequent growth of additional tumors(metastasis) in different tissues. The detection of CTCs may have important prognostic and therapeutic implications but, because their number is very small, these cells are not easily detected. Circulating tumor cells are found in the order of 10–100 CTCs per m L of whole blood in patients with metastatic disease. Isolation of tumor cells circulating in the blood stream, by immobilizing them on surfaces functionalized with bio-active coating within microfluidic devices,presents an interdisciplinary challenge requiring expertise in different research areas: cell biology, surface chemistry, fluid mechanics and microsystem technology.We first review the fundamental of cell biology of CTCs and summarize the key microfluidic techniques for isolation of CTCs via cell-ligand interactions, magnetic interactions, filtration; detection and enumeration of CTCs; in vivo CTCs imaging.

<p>随着油田开采时间的增长，产出液中含水率逐年增加，部分井液的含水率高达95%以上，给目前已有的处理工艺带来新的挑战。为了解决这些问题，急需研发新型的油水分离技术，以解决传统技术所遇到的瓶颈。本文结合目前油气开发的新需求，系统地介绍了油水分离的技术现状，讨论了含油污水深度处理技术的特点，分析了未来油水分离技术的发展趋势。同时，结合力学研究所研制的新型管道式油水分离技术，详细介绍了柱型分离、导流片型分离、以及T型管分离等新技术，提出了新型管道式分离技术具有的技术优势，可解决稠油开采、海底作业、以及井下分离等难题，指明了技术发展方向。</p>

Investigations on irradiation hardening of metallic materials have much sig- nificance for the design of anti-irradiation materials and engineering applications. Both irradiation-induced defects and gaseous impurities produced by nuclear reactions have dra- matic irradiation effects on the mechanical properties of materials, which include irradiation hardening, irradiation embrittlement and irradiation creep, etc. In this paper we are con- cerned with irradiation hardening, i.e., the strength of materials increases with irradiation, under low irradiation doses and low temperatures of T < 0.3 Tm with Tm the melting temper- ature. Besides, other factors such as the grain size, the grain boundary and the temperature affect mechanical behaviors of irradiated polycrystalline materials. The study of irradia- tion hardening of metallic materials is a multi-scale problem, for which the macroscopic mechanical behaviors of irradiated materials are determined by both the change of interior structures with irradiation at micro-scale and the interactions among irradiated grains at meso-scale. This paper reviews experimental results, numerical simulations and theoretical models for irradiation hardening of metallic materials. Some scientific problems for future study are also presented.

The discovery of coherent structures in turbulent shear flows is one of the most important advances in turbulence research of the last century. These large-scale structures play important role in the physics of wall turbulence, and suggest a new direction for turbulence control. High skin friction in wall-bounded turbulent flows is closely associated with the coherent structures in the near-wall region. The control strategy based on the near-wall physics successfully achieves drag reduction, yet becomes less effective as the Reynolds number increases. It was discovered recently that large-scale coherent motions exist in the outer layer of the high-Reynolds number wall turbulence. These motions have important influence on turbulence in the near-wall region and the skin friction, and bring new challenges to the control of turbulent flow at high Reynolds number. In the present paper, we briefly review the research history on coherent structures in wall turbulence, and mainly focus on dis- cussing the near-wall coherent structures and their control mechanism, the recent research developments on the large-scale motions in the outer region of high-Reynolds number wall turbulence, and the key issues concerning the drag-reduction control of the high-Reynolds number turbulent flows.

微流控技术及微流控器件是近年来发展迅速的多学科交叉研究领域. 相比于传统方法,微流控技术能够实现对微量多相流体的精准操控,可应用于化学分析、先进材料合成、蛋白质结晶、单细胞培育及检测、信息处理等领域.该文回顾微流控器件中的多相流动现象,概述其所涉及的流体力学机理,阐述实现多相微流控的各种方法,并分析多相微流控技术的应用现状及面临的挑战,最后总结针对多相微流动问题的数值模拟方法和实验测量技术,展望多相微流控器件的研究方向及应用前景.

Magneto-sensitive smart soft materials are a class of multi-functional compos-ite materials prepared by dispersing micrometer or nanometer sized magnetic particles into di®erent carrier matrix. As external magnetic field may control the rheological properties in a continuous, rapid and reversible manner, these materials have wide applications in con-struction, vibration control, automotive industry, etc. In this paper, we first introduce the history and classification of magneto-sensitive smart soft materials, and analyze the charac-teristics and existing scientific issues for di®erent kinds of such materials. Then we discuss the state-of-the-art for experimental and theoretical studies of the magnetorheological mech-anism. Finally, we propose some future trends in this smart material development aiming at practical applications.

The study of natural convection in a differentially heated cavity is of practical significance in nature and industry. It is of scientific value to review the studies of natural convection flows, their flow properties, dynamical mechanisms, dimensional controlling parameter dependencies and heat transfer driven by the horizontal temperature gradient in the cavity. As shown by previous studies, the development of natural convection suddenly enforced by the horizontal temperature gradient between the sidewalls of the cavity includes an initial stage, a transitional stage and a steady or a quasi-steady stage. The transient flows in the different stages are determined by the Rayleigh number, the Prandtl number and the aspect ratio. The flow in the steady or quasi-steady stage could be a steady laminar, a periodic or a turbulent flow. In addition, the studies of instability and turbulence of natural convection in the cavity are reviewed, and the prospects for the study of natural convection in the cavity are presented.

More than 80% of world energy is converted by combustion. Development of efficient next generation advanced engines by using alternative fuels and operating at extreme conditions is one of the most important solutions to increase energy sustainability. To realize the advanced engine design, the challenges in combustion research are therefore to advance fundamental understanding of combustion chemistry and dynamics from molecule scales to engine scales and to develop quantitatively predictive tools and innovative combustion technologies. This review will present the recent progresses and technical challenges in fundamental combustion research in seven areas including advanced engine concepts using low temperature fuel chemistry, new combustion phenomena in extreme conditions, alternative and surrogate fuels, multi-scale modeling, high pressure combustion kinetics, experimental methods and advanced combustion diagnostics Firstly, new engine concepts such as the Homogeneous Charge Compression Ignition (HCCI), Reactivity Controlled Compression Ignition (RCCI), and pressure gain combustion will be introduced. The impact of low temperature combustion chemistry of fuels on combustion in advanced engines will be demonstrated. This is followed by the discussions of the needs of fundamental combustion research for new engine technologies. Secondly, combustion phenomena and flame regimes involving new combustion concepts such as fuel and thermal stratifications, plasma assisted combustion, and cool flames at extreme conditions will be analyzed. Thirdly, alternative fuels and methodologies to formulate surrogate fuel mixtures to model the target combustion properties of real fuels will be presented. A new concept of radical index and transport weighted enthalpy will be introduced to rank the fuel reactivity and to assess the impact of molecular structure on combustion properties The success and limitations of the current surrogate fuel models will be discussed by using jet fuels and biodiesels as examples. Fourthly, the difficulty of modeling large kinetic mechanism of real fuel will be discussed The multi-time scale (MTS) method and the correlated dynamic adaptive chemistry (CO-DAC) method for kinetic model reduction and computationally efficient modeling will be compared and analyzed. Fifthly, the progress and challenges of high pressure combustion kinetics for hydrogen and larger hydrocarbons will be discussed. The important pressuredependent reaction pathways and key intermediate species at high pressure will be analyzed. Fundamental experimental methods for combustion and their uncertainties in acquiring combustion properties for the validation of kinetic mechanism will be discussed. Finally, recent progress in diagnostics of HO2, H2O2, RO2, ketohydroperoxide, and other key intermediate species for high pressure kinetic mechanism development will be summarized. Conclusions and opportunities of future combustion research will be made.