Acta Mechanica Sinica
The Journal covers all disciplines in the field of theoretical and applied mechanics, including solid mechanics, fluid mechanics, dynamics and control, and biomechanics. It explores analytical, computational and experimental progresses in all areas of mechanics. The Journal also encourages research in interdisciplinary subjects, and servess...
CN 11-2063/O3
ISSN 0567-7718(Print)
ISSN 1614-3116(Online)
Editors-in-Chief:
Professor Tianjian Lu
Professor Wei Shyy
Professor Zhigang Suo
Impact Factor: 0.832
Citation: Acta Mech. Sin.
Frequency: Bimonthly
Focus Articles

 
Editorial & News
 
Current Issue Online First Archive Most Read Articles Most Downloaded Articles
Acta Mechanica Sinica--2016, 32 (4)   Published: 20 July 2016
FLUID MECHANICS
Structural subgrid-scale modeling for large-eddy simulation: A review
Hao Lu, Christopher J. Rutland
Abstract

Accurately modeling nonlinear interactions in turbulence is one of the key challenges for large-eddy simulation (LES) of turbulence. In this article, we review recent studies on structural subgrid scale modeling, focusing on evaluating how well these models predict the effects of small scales. The article discusses a priori and a posteriori test results. Other nonlinear models are briefly discussed, and future prospects are noted.

Downstream pressure and elastic wall reflection of droplet flow in a T-junction microchannel
Yan Pang, Zhaomiao Liu, Fuwang Zhao
Abstract

This paper discusses pressure variation on a wall during the process of liquid flow and droplet formation in a T-junction microchannel. Relevant pressure in the channel, deformation of the elastic wall, and responses of the droplet generation are analyzed using a numerical method. The pressure difference between the continuous and dispersed phases can indicate the droplet-generation period. The pressure along the channel of the droplet flow is affected by the position of droplets, droplet-gen...

Delayed detached eddy simulations of fighter aircraft at high angle of attack
Guoliang Xu, Xiong Jiang, Gang Liu
Abstract

Themassively separated flows over a realistic aircraft configuration at 40°, 50°, and 60° angles of attack are studied using the delayed detached eddy simulation (DDES). The calculations are carried out at experimental conditions corresponding to a mean aerodynamic chord-based Reynolds number of 8.93×10^5 and Mach number of 0.088. The influence of the grid size is investigated using two grids, 20.0×10^6 cells and 31.0×10^6 cells. ...

SOLID MECHANICS
Energy corrugation in atomic-scale friction on graphite revisited by molecular dynamics simulations
Xiao-Yu Sun, Yi-Zhou Qi, Wengen Ouyang, Xi-Qiao Feng, Qunyang Li
Abstract

Although atomic stick-slip friction has been extensively studied since its first demonstration on graphite, the physical understanding of this dissipation-dominated phenomenon is still very limited. In this work, we perform molecular dynamics (MD) simulations to study the frictional behavior of a diamond tip sliding over a graphite surface. In contrast to the common wisdom, our MD results suggest that the energy barrier associated lateral sliding (known as energy corrugation) comes not only f...

Quantitative law of diffusion induced fracture
H.-J. Lei, H.-L.Wang, B. Liu, C.-A.Wang
Abstract

Through dimension analysis, an almost analytical model for the maximum diffusion induced stress (DIS) and critical temperature (or concentration) difference at which cracks begin to initiate in the diffusion process is developed. It interestingly predicts that the spacing of diffusion-induced cracks is constant, independent of the thickness of specimen and the temperature difference. These conclusions are validated by our thermal shock experiments on alumina plates. Furthermore, the proposed ...

A comparative study of piezoelectric unimorph and multilayer actuators as stiffness sensors via contact resonance
Ji Fu, Fa-Xin Li
Abstract

Piezoelectric bar-shaped resonators were proposed to act as hardness sensors in the 1960s and stiffness sensors in the 1990s based on the contact impedance method. In this work, we point out that both multilayer and unimorph (or bimorph) piezoelectric actuators could act as stiffness/modulus sensors based on the principle of mechanical contact resonance. First, the practical design and the performance of a piezoelectric unimorph actuator-based stiffness sensor were presented. Then the working...

A numerical approach for pressure transient analysis of a vertical well with complex fractures
Yizhao Wan, Yuewu Liu, Wenchao Liu, Guofeng Han, Congcong Niu
Abstract

A new well test model for a vertical fractured well is developed based on a discrete-fracture model in which the fractures are discretized as one dimensional (1-D) entities. The model overcomes the weakness of complex meshing, a large number of grids, and instability in conventional stripe-fracture models. Then, the discrete-fracture model is implemented using a hybrid element finite-element method. Triangular elements are used formatrix and line elements for the fractures. The finite element...

Plate/shell topological optimization subjected to linear buckling constraints by adopting composite exponential filtering function
Hong-Ling Ye, Wei-Wei Wang, Ning Chen, Yun-Kang Sui
Abstract

In this paper, a model of topology optimization with linear buckling constraints is established based on an independent and continuous mapping method to minimize the plate/shell structure weight. A composite exponential function (CEF) is selected as filtering functions for element weight, the element stiffness matrix and the element geometric stiffness matrix, which recognize the design variables, and to implement the changing process of design variables from “discrete” to “...

Numerical simulations of the process of multiple shock-flame interactions
Hua Jiang, Gang Dong, Xiao Chen, Jin-Tao Wu
Abstract

Based on a weighted essentially nonoscillatory scheme, the multiple interactions of a flame interface with an incident shock wave and its reshock waves are numerically simulated by solving the compressible reactive Navier- Stokes equations with a single-step Arrhenius chemical reaction. The two-dimensional sinusoidally perturbed premixed flames with different initial perturbed amplitudes are used to investigate the effect of the initial perturbation on the flame evolutions. The results show t...

Analytical and finite-element study of optimal strain distribution in various beam shapes for energy harvesting applications
B. L. Ooi, J. M. Gilbert, A. Rashid A. Aziz
Abstract

Owing to the increasing demand for harvesting energy from environmental vibration for use in self-powered electronic applications, cantilever-based vibration energy harvesting has attracted considerable interest from various parties and has become one of the most common approaches to converting redundant mechanical energy into electrical energy. As the output voltage produced from a piezoelectric material depends largely on the geometric shape and the size of the beam, there is a need to mode...

Structure dependent elastic properties of supergraphene
Juan Hou, Zhengnan Yin, Yingyan Zhang, Tien-Chong Chang
Abstract

Complete replacement of aromatic carbon bonds in graphene by carbyne chains gives rise to supergraphene whose mechanical properties are expected to depend on its structure. However, this dependence is to date unclear. In this paper, explicit expressions for the in-plane stiffness and Poisson's ratio of supergraphene are obtained using a molecular mechanics model. The theoretical results show that the in-plane stiffness of supergraphene is drastically (at least one order) smaller than that of ...

The comparative analysis of rocks' resistance to forward-slanting disc cutters and traditionally installed disc cutters
Zhao-Huang Zhang, Sun Fei, Meng Liang
Abstract

At present, disc cutters of a full face rock tunnel boring machine are mostly mounted in the traditional way. Practical use in engineering projects reveals that this installation method not only heavily affects the operation life of disc cutters, but also increases the energy consumption of a full face rock tunnel boring machine. To straighten out this issue, therefore, a rock-breaking model is developed for disc cutters' movement after the research on the rock breaking of forward-slanting di...

A criterion for high-cycle fatigue life and fatigue limit prediction in biaxial loading conditions
Łukasz Pejkowski, Dariusz Skibicki
Abstract

This paper presents a criterion for high-cycle fatigue life and fatigue strength estimation under periodic proportional and non-proportional cyclic loading. The criterion is based on the mean and maximum values of the second invariant of the stress deviator. Important elements of the criterion are: function of the non-proportionality of fatigue loading and the materials parameter that expresses the materials sensitivity to non-proportional loading. The methods for the materials parameters det...

DYNAMICS, VIBRATION, AND CONTROL
Modal parameter identification of flexible spacecraft using the covariance-driven stochastic subspace identification (SSI-COV) method
Yong Xie, Pan Liu, Guo-Ping Cai
Abstract

In this paper, the on-orbit identification of modal parameters for a spacecraft is investigated. Firstly, the coupled dynamic equation of the system is established with the Lagrange method and the stochastic state-space model of the system is obtained. Then, the covariance-driven stochastic subspace identification (SSI-COV) algorithm is adopted to identify the modal parameters of the system. In this algorithm, it just needs the covariance of output data of the system under ambient excitation ...

New method for oblique impact dynamics research of a flexible beam with large overall motion considering impact friction force
W. Yuan, L. Li, D. G. Zhang, J. Z. Hong
Abstract

A flexible beam with large overall rotating motion impacting with a rigid slope is studied in this paper. The tangential friction force caused by the oblique impact is analyzed. The tangential motion of the system is divided into a stick state and a slip state. The contact constraint model and Coulomb friction model are used respectively to deal with the two states. Based on this hybrid modeling method, dynamic equations of the system, which include all states (before, during, and after the c...

Vibration analysis of hard-coated composite beam considering the strain dependent characteristic of coating material
W. Sun, Y. Liu
Abstract

The strain dependent characteristics of hard coatings make the vibration analysis of hard-coated composite structure become a challenging task. In this study, the modeling and the analysis method of a hard-coated composite beam was developed considering the strain dependent characteristics of coating material. Firstly, based on analyzing the properties of hard-coating material, a high order polynomial was adopted to characterize the strain dependent characteristics of coating materials. Then,...

Interval arithmetic operations for uncertainty analysis with correlated interval variables
Chao Jiang, Chun-Ming Fu, Bing-Yu Ni, Xu Han
Abstract

A new interval arithmetic method is proposed to solve interval functions with correlated intervals through which the overestimation problem existing in interval analysis could be significantly alleviated. The correlation between interval parameters is defined by the multidimensional parallelepiped model which is convenient to describe the correlative and independent interval variables in a unified framework. The original interval variables with correlation are transformed into the standard sp...

Optimal design of near-Earth asteroid sample-return trajectories in the Sun-Earth-Moon system
Shengmao He, Zhengfan Zhu, Chao Peng, Jian Ma, Xiaolong Zhu, Yang Gao
Abstract

In the 6th edition of the Chinese Space Trajectory Design Competition held in 2014, a near-Earth asteroid sample-return trajectory design problem was released, in which the motion of the spacecraft is modeled in multi-body dynamics, considering the gravitational forces of the Sun, Earth, and Moon. It is proposed that an electric-propulsion spacecraft initially parking in a circular 200-km-altitude low Earth orbit is expected to rendezvous with an asteroid and carry as much sample as possible ...

ERRATUM
Erratum to: Control of surface wettability via strain engineering
Wei Xiong, Jefferson Zhe Liu, Zhi-Liang Zhang, Quan-Shui Zheng
Abstract
Erratum to: Multi-scale morphology analysis of acoustic emission signal and quantitative diagnosis for bearing fault
Wen-Jing Wang, Ling-Li Cui, Dao-Yun Chen
Abstract
 
v
Copyright © Acta Mechanica Sinica Editorial Office
Address: No.15 Bei Si Huan Xi Road,Beijing 100190,China
Telephone: +86-(0)10-62536271 Fax:+86-(0)10-82543907
E-mail: actams@cstam.org.cn
Technical support: Beijing Magtech Co.ltd support@magtech.com.cn