Applied Mathematics and Mechanics (English Edition)

Thermal buckling analysis of truss-core sandwich plates

陈继伟刘咏泉刘伟苏先樾

2013, 34(10): 1177-1186. doi:10.1007/s10483-013-1737-7

摘要 ( 778 )

PDF (316KB) ( 852 )

相关文章 | 多维度评价

Truss-core sandwich plates have received much attention in virtue of the high values of strength-to-weight and stiffness-to-weight as well as the great ability of impulseresistance recently. It is necessary to study the stability of sandwich panels under the influence of the thermal load. However, the sandwich plates are such complex threedimensional (3D) systems that direct analytical solutions do not exist, and the finite element method (FEM) cannot represent the relationship between structural parameters and mechanical properties well. In this paper, an equivalent homogeneous continuous plate is idealized by obtaining the effective bending and transverse shear stiffness based on the characteristics of periodically distributed unit cells. The first order shear deformation theory for plates is used to derive the stability equation. The buckling temperature of a simply supported sandwich plate is given and verified by the FEM. The effect of related parameters on mechanical properties is investigated. The geometric parameters of the unit cell are optimized to attain the maximum buckling temperature. It is shown that the optimized sandwich plate can improve the resistance to thermal buckling significantly.

Nanoscale finite element models for vibrations of single-walled carbon nanotubes: atomistic versus continuum

R. ANSARI S. ROUHI M. ARYAYI

2013, 34(10): 1187-1200. doi:10.1007/s10483-013-1738-9

摘要 ( 815 )

PDF (865KB) ( 475 )

相关文章 | 多维度评价

null

Basic solutions of multiple parallel symmetric mode-III cracks in functionally graded piezoelectric/piezomagnetic material plane

泮世东周振功吴林志

2013, 34(10): 1201-1224. doi:10.1007/s10483-013-1739-6

摘要 ( 615 )

PDF (653KB) ( 561 )

相关文章 | 多维度评价

The Schmidt method is adopted to investigate the fracture problem of multiple parallel symmetric and permeable finite length mode-III cracks in a functionally graded piezoelectric/piezomagnetic material plane. This problem is formulated into dual integral equations, in which the unknown variables are the displacement jumps across the crack surfaces. In order to obtain the dual integral equations, the displacement jumps across the crack surfaces are directly expanded as a series of Jacobi polynomials. The results show that the stress, the electric displacement, and the magnetic flux intensity factors of cracks depend on the crack length, the functionally graded parameter, and the distance among the multiple parallel cracks. The crack shielding effect is also obviously presented in a functionally graded piezoelectric/piezomagnetic material plane with multiple parallel symmetric mode-III cracks.

High-efficiency improved symmetric successive over-relaxation preconditioned conjugate gradient method for solving large-scale finite element linear equations

李根唐春安李连崇

2013, 34(10): 1225-1236. doi:10.1007/s10483-013-1740-x

摘要 ( 712 )

PDF (435KB) ( 561 )

相关文章 | 多维度评价

Fast solving large-scale linear equations in the finite element analysis is a classical subject in computational mechanics. It is a key technique in computer aided engineering (CAE) and computer aided manufacturing (CAM). This paper presents a high-efficiency improved symmetric successive over-relaxation (ISSOR) preconditioned conjugate gradient (PCG) method, which maintains the convergence and inherent parallelism consistent with the original form. Ideally, the computation can be reduced nearly by 50% as compared with the original algorithm. It is suitable for high-performance computing with its inherent basic high-efficiency operations. By comparing with the numerical results, it is shown that the proposed method has the best performance.

Hybrid discrete-continuum model of tumor growth considering capillary points

吕杰许世雄姚伟周瑜龙泉

2013, 34(10): 1237-1246. doi:10.1007/s10483-013-1741-9

摘要 ( 676 )

PDF (662KB) ( 468 )

相关文章 | 多维度评价

A hybrid discrete-continuum model of tumor growth in the avascular phase considering capillary points is established. The influence of the position of capillary points on tumor growth is also studied by simulation. The results of the dynamic tumor growth and the distribution of oxygen, matrix-degrading enzymes, and extracellular matrixconcentration in the microenvironment with respect to time are shown by graphs. The relationships between different oxygenated environments and the numbers of surviving, dead, proliferative, and quiescent tumor cells are also investigated.

Effect of double dispersion on non-Darcy mixed convective flow over vertical surface embedded in porous medium

A. A. AFIFY N. S. ELGAZERY

2013, 34(10): 1247-1262. doi:10.1007/s10483-013-1742-8

摘要 ( 801 )

PDF (458KB) ( 759 )

相关文章 | 多维度评价

A numerical study of a non-Darcy mixed convective heat and mass transfer flow over a vertical surface embedded in a porous medium under the effects of double dispersion, melting, and thermal radiation is investigated. The set of governing boundary layer equations and the boundary conditions is transformed into a set of coupled nonlinear ordinary differential equations with the relevant boundary conditions. The transformed equations are solved numerically by using the Chebyshev pseudospectral method. Comparisons of the present results with the existing results in the literature are made, and good agreement is found. Numerical results for the velocity, temperature, concentration profiles, and local Nusselt and Sherwood numbers are discussed for various values of physical parameters.

MHD non-Newtonian micropolar fluid flow and heat transfer in channel with stretching walls

M. ASHRAF N. JAMEEL K. ALI

2013, 34(10): 1263-1276. doi:10.1007/s10483-013-1743-6

摘要 ( 933 )

PDF (635KB) ( 620 )

相关文章 | 多维度评价

A study is presented for magnetohydrodynamics (MHD) flow and heat transfer characteristics of a viscous incompressible electrically conducting micropolar fluid in a channel with stretching walls. The micropolar model introduced by Eringen is used to describe the working fluid. The transformed self similar ordinary differential equations together with the associated boundary conditions are solved numerically by an algorithm based on quasi-linearization and multilevel discretization. The effects of some physical parameters on the flow and heat transfer are discussed and presented through tables and graphs. The present investigations may be beneficial in the flow and thermal control of polymeric processing.

Limit cycle oscillation suppression of 2-DOF airfoil using nonlinear energy sink

郭虎伦陈予恕杨天智

2013, 34(10): 1277-1290. doi:10.1007/s10483-013-1744-7

摘要 ( 757 )

PDF (828KB) ( 904 )

相关文章 | 多维度评价

This paper presents a novel mechanical attachment, i.e., nonlinear energy sink (NES), for suppressing the limit cycle oscillation (LCO) of an airfoil. The dynamic responses of a two-degree-of-freedom (2-DOF) airfoil coupled with an NES are studied with the harmonic balance method. Different structure parameters of the NES, i.e., mass ratio between the NES and airfoil, NES offset, NES damping, and nonlinear stiffness in the NES, are chosen for studying the effect of the LCO suppression on an aeroelastic system with a supercritical Hopf bifurcation or subcritical Hopf bifurcation, respectively. The results show that the structural parameters of the NES have different influence on the supercritical Hopf bifurcation system and the subcritical Hopf bifurcation system.

Weak KKM theorems in generalized finitely continuous space with applications

方敏王磊

2013, 34(10): 1291-1296. doi:10.1007/s10483-013-1745-8

摘要 ( 704 )

PDF (145KB) ( 644 )

相关文章 | 多维度评价

Some new weak Knaster-Kuratouski-Mazurkiewicz (KKM) theorems are proved under the noncompact situation in the generalized finitely continuous space (GFCspace) without any convexity. As applications, the minimax inequalities of the Ky Fan type are also given under some suitable conditions. The results unify and generalize some known results in recent literatures.

On Hardy-type integral inequalities

冷拓冯勇

2013, 34(10): 1297-1304. doi:10.1007/s10483-013-1746-x

摘要 ( 611 )

PDF (137KB) ( 502 )

相关文章 | 多维度评价

The Hardy integral inequality is one of the most important inequalities in analysis. The present paper establishes some new Copson-Pachpatte (C-P) type inequalities, which are the generalizations of the Hardy integral inequalities on binary functions.

当期目录