V. Filonova¹, Y. Liu¹, M. Bailakanavar¹, J. Fish¹, Z. Yuan²

CMC-Computers, Materials & Continua, Vol.34, No.3, pp. 177-198, 2013, DOI:10.3970/cmc.2013.034.177

Abstract A corotational formulation for reduced order homogenization is presented. While in principle the proposed method is valid for problems with arbitrary large strains, it is computational advantageous over the classical direct computational homogenization method for large rotations but moderate unit cell distortions. We validate the method for several large deformation problems including: (i) hat-section composite beam with two-dimensional chopped tow composite architecture, (ii) polyethylene microstructure consisting of 'hard' and 'soft' domains (segments), and (iii) fiber framework called fiberform either embedded or not in an amorphous matrix. More >

CHAOJUN TANG¹, XUE WU¹, LINQI YE^1,2, XIANG XIE¹, GUIXUE WANG^1*

BIOCELL, Vol.36, No.3, pp. 97-104, 2012, DOI:10.32604/biocell.2012.36.097

Abstract Devices for the rotational culture of cells and the study of biological reactions have been widely applied in tissue engineering. However, there are few reports exploring the effects of rotational culture on cell morphology, nitric oxide (NO) production, and cell cycle of the endothelial cells from human umbilical vein on the stent surface. This study focuses on these parameters after the cells are seeded on the stents. Results showed that covering of stents by endothelial cells was improved by rotational culture. NO production decreased within 24 h in both rotational and static culture groups. In More >

Y.C. Cai¹, S.N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.83, No.3, pp. 249-274, 2012, DOI:10.3970/cmes.2012.083.249

Abstract This paper presents a very simple finite element method for geometrically nonlinear large rotation analyses of plate/shell structures comprising of thin members. A fully nonlinear theory of deformation is employed in the updated Lagrangian reference frame of each plate element, to account for bending, stretching and torsion of each element. An assumed displacement approach, based on the Discrete Kirchhoff Theory (DKT) over each element, is employed to derive an explicit expression for the (18x18) symmetric tangent stiffness matrix of the plate element in the co-rotational reference frame. The finite rotation of the updated Lagrangian reference… More >

Saptarshi Sasmal¹, K. Ramanjaneyulu²

Structural Durability & Health Monitoring, Vol.7, No.4, pp. 253-282, 2011, DOI:10.3970/sdhm.2011.007.253

Abstract This paper proposes a methodology for damage detection in beam like structures using vibration characteristics obtained from transfer matrix technique. At first, vibration characteristics of beam-like structure have been determined with the help of a computer program developed based on the formulations presented in this paper. Then, a detailed study has been carried out to categorise the influence of damage on frequency and mode shape (both displacement and rotational) information. For a structure with known magnitude and location of damage(s), frequencies and mode shape information are obtained and the same has been used in determining… More >

K.Y.Sze, Y.X.Zhou

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.3, pp. 91-92, 2011, DOI:10.3970/icces.2011.017.091

Abstract In this paper, new rotation-free beam and shell models are presented. Unlike the finite element models, rotation-free models employ integration domains which are smaller than the domains of influence. Hence, they are sometimes known as overlapping elements. The present linear straight beam and plate models are the same as those of Phaal & Calladine in the sense that quadratic interpolation are employed to construct the transverse deflection. Nevertheless, Phaal & Calladine turned to a hinged-angle approach for the linear curved beam and shell models and did not present the geometric nonlinear models. In our formulation,… More >

R. Faruk Yokseler

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 105-106, 2011, DOI:10.3970/icces.2011.016.105

Abstract The mid surface of undeformed rubber-like shells undergoing finite rotations and finite strains has been considered to be the reference surface of the undeformed configuration. There have been two different definitions for the reference surface of deformed rubber-like shells, undergoing finite rotations and finite strains, used by several researchers. In this study, some comments on the stress-resultants defined relative to the mentioned two reference surfaces of deformed incompressible rubber-like shells under axisymmetrical effects, considering transverse normal and transverse shear deformations, are presented. More >

Norman Hecht

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.1, pp. 25-26, 2011, DOI:10.3970/icces.2011.016.025

Abstract The torque-free rotation of a rigid body has long been a topic of interest to physicists, mathematicians and engineers, including Euler in the 18th century, and continuing to the present day. Numerical solutions to Euler's equations are easy to achieve in an era of cheap computation, but classic solutions to the problem have used principles of angular momentum and energy to develop geometric insights to the problem. Static diagrams can help display these insights, but modern computer graphics hardware and software can truly bring these solutions to life via user-controlled animation.
Besides making visible such abstractions… More >

Yi W. Wan¹, Huan J. Keh²

CMES-Computer Modeling in Engineering & Sciences, Vol.74, No.2, pp. 109-138, 2011, DOI:10.3970/cmes.2011.074.109

Abstract The steady rotation of an axially symmetric particle about its axis of revolution normal to two plane walls at an arbitrary position between them in a viscous fluid is studied theoretically in the limit of small Reynolds number. The fluid is allowed to slip at the surface of the particle. A method of distribution of a set of spherical singularities along the axis of revolution inside a prolate particle or on the fundamental disk within an oblate particle is used to find the general solution for the fluid velocity distribution that satisfies the boundary conditions… More >

G. M. Kulikov¹, S. V. Plotnikova¹

CMC-Computers, Materials & Continua, Vol.23, No.3, pp. 233-264, 2011, DOI:10.3970/cmc.2011.023.233

Abstract This paper presents a robust non-linear piezoelectric exact geometry (EG) four-node solid-shell element based on the higher-order 9-parameter equivalent single-layer (ESL) theory, which permits one to utilize 3D constitutive equations. The term EG reflects the fact that coefficients of the first and second fundamental forms of the reference surface are taken exactly at each element node. The finite element formulation developed is based on a new concept of interpolation surfaces (I-surfaces) inside the shell body. We introduce three I-surfaces and choose nine displacements of these surfaces as fundamental shell unknowns. Such choice allows us to… More >

Y.C. Cai^1,2, J.K. Paik³, S.N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.61, No.3, pp. 273-312, 2010, DOI:10.3970/cmes.2010.061.273

Abstract This paper presents an elementary finite element method for geometrically nonlinear large rotation analyses of built-up plate/shell structures comprising of thin members. The tangent stiffness matrix of the element in the updated Lagrangian co-rotational reference frame is developed, based on the von Karman nonlinear theory of plates, and the Reissner variational principle, allowing for unsymmetric stresses and drilling rotations, useful in the analysis of built-up plate and shell structure. The finite rotation of the co-rotational reference frame relative to a globally fixed Cartesian frame, is simply determined from the finite displacement vectors of the nodes… More >