Yang Xia^*, Luting Deng, Jian Zhao

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 605-626, 2020, DOI:10.32604/cmes.2020.010204

Abstract Geometric fitting based on discrete points to establish curve structures is an important problem in numerical modeling. The purpose of this paper is to investigate the geometric fitting method for curved beam structure from points, and to get high-quality parametric model for isogeometric analysis. A Timoshenko beam element is established for an initially curved spacial beam with arbitrary curvature. The approximation and interpolation methods to get parametric models of curves from given points are examined, and three strategies of parameterization, meaning the equally spaced method, the chord length method and the centripetal method are considered. The influences of the different… More >

Sanghyun Shim, Kwangjin Kim, Sangchul Lee, Sangho Ko, Jayoung Kang, Dongyoung Rew, Gwanghyeok Ju

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 73-74, 2011, DOI:10.3970/icces.2011.019.073

Abstract The aim of this paper is to discuss the main issues related to modeling and simulation of the Korean lunar module. Lunar module usually consists of a rigid platform, attitude control actuators and a fuel tank. For dynamical modeling, we first assumed the lunar module as a rigid body and derived equations of motion by considering allocation of reaction thrusters and reaction wheel assembly(RWA). Fuel sloshing in lunar module and its influence on attitude dynamics are an important issue in the research field of space technology. In order to include the effect of fuel sloshing on the dynamics, we model… More >

Jong-Kook Cha¹, Jin-Rae Cho¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.3, pp. 129-134, 2008, DOI:10.3970/icces.2008.007.129

Abstract Sloshing flow is formulated based on the linearized potential flow theory, while an artificial damping term is employed into the kinematic free-surface condition to reflect the eminent dissipation effect in resonant sloshing. Through the numerical analysis of sloshing frequency response with respect to the number, location and opening width of baffle, the sloshing damping characteristics by baffle are parametrically investigated. More >

T.-L. Zhu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.3, pp. 107-112, 2008, DOI:10.3970/icces.2008.007.107

Abstract A modeling method for flapwise and chordwise bending vibration analysis for rotating Timoshenko beams is introduced. For the modeling method shear and the rotary inertia effects are correctly judged based on \textit {Timoshenko beam theory}. Equations of motion of continuous models are derived from a modeling method which employs hybrid deformation variables. The equations thus derived are transmitted into dimensionless forms. The effects of dimensionless parameters on the modal characteristics of the Timoshenko beams are successfully examined through numerical study. In particular, eigenvalue loci veering phenomena and integrated mode shape critical deviations are contemplated and examined in this work. More >

V. Panchore¹, R. Ganguli², S. N. Omkar³

CMES-Computer Modeling in Engineering & Sciences, Vol.108, No.4, pp. 215-237, 2015, DOI:10.3970/cmes.2015.108.215

Abstract A rotating Timoshenko beam free vibration problem is solved using the meshless local Petrov-Galerkin method. A locking-free shape function formulation is introduced with an improved radial basis function interpolation and the governing differential equations of the Timoshenko beam are used instead of the alternative formulation used by Cho and Atluri (2001). The locking-free approximation overcomes the problem of ill conditioning associated with the normal approximation. The radial basis functions satisfy the Kronercker delta property and make it easier to apply the essential boundary conditions. The mass matrix and the stiffness matrix are derived for the meshless local Petrov-Galerkin method. Results… More >

Vinita Chellappan¹, S. Gopalakrishnan¹ and V. Mani¹

CMES-Computer Modeling in Engineering & Sciences, Vol.97, No.2, pp. 131-174, 2014, DOI:10.3970/cmes.2014.097.131

Abstract The paper discusses the frequency domain based solution for a certain class of wave equations such as: a second order partial differential equation in one variable with constant and varying coefficients (Cantilever beam) and a coupled second order partial differential equation in two variables with constant and varying coefficients (Timoshenko beam). The exact solution of the Cantilever beam with uniform and varying cross-section and the Timoshenko beam with uniform cross-section is available. However, the exact solution for Timoshenko beam with varying cross-section is not available. Laplace spectral methods are used to solve these problems exactly in frequency domain. The numerical… More >

A.E. Kampitsis¹, E.J. Sapountzakis²

CMES-Computer Modeling in Engineering & Sciences, Vol.103, No.6, pp. 367-409, 2014, DOI:10.3970/cmes.2014.103.367

Abstract In this paper a Boundary Element Method (BEM) is developed for the geometrically nonlinear inelastic analysis of Timoshenko beams of arbitrary doubly symmetric simply or multiply connected constant cross-section, resting on inelastic tensionless Winkler foundation. The beam is subjected to the combined action of arbitrarily distributed or concentrated transverse loading and bending moments in both directions as well as to axial loading, while its edges are subjected to the most general boundary conditions. To account for shear deformations, the concept of shear deformation coefficients is used. A displacement based formulation is developed and inelastic redistribution is modeled through a distributed… More >

Hao Zuo^1,2, Zhi-Bo Yang^1,2,3, Xue-Feng Chen^1,2, Yong Xie⁴, Xing-Wu Zhang^1,2, Yue Liu⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.100, No.6, pp. 477-506, 2014, DOI:10.3970/cmes.2014.100.477

Abstract The application of B-spline wavelet on the interval (BSWI) finite element method for static, free vibration and buckling analysis in functionally graded (FG) beam is presented in this paper. The functionally graded material (FGM) is a new type of heterogeneous composite material with material properties varying continuously throughout the thickness direction according to power law form in terms of volume fraction of material constituents. Different from polynomial interpolation used in traditional finite element method, the scaling functions of BSWI are employed to form the shape functions and construct wavelet-based elements. Timoshenko beam theory and Hamilton’s principle are adopted to formulate… More >

A.S Vinod Kumar, Ranjan Ganguli²

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.6, pp. 443-474, 2012, DOI:10.3970/cmes.2012.088.443

Abstract The governing differential equation of a rotating beam becomes the stiff-string equation if we assume uniform tension. We find the tension in the stiff string which yields the same frequency as a rotating cantilever beam with a prescribed rotating speed and identical uniform mass and stiffness. This tension varies for different modes and are found by solving a transcendental equation using bisection method. We also find the location along the rotating beam where equivalent constant tension for the stiff string acts for a given mode. Both Euler-Bernoulli and Timoshenko beams are considered for numerical results. The results provide physical insight… More >

Changsheng Wang¹, Ping Hu^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.5, pp. 325-350, 2012, DOI:10.3970/cmes.2012.088.325

Abstract Based on the Reissner-Mindlin plate theory, two 3-node triangular flat shell elements QCS31 and QCS32 are proposed by using Timoshenko's beam function within the framework of quasi-conforming technique. The exact displacement function of the Timoshenko's beam is used as the displacement on the element boundary in the bending part and the interpolated inner field function is also derived by the function. In the shear part the re-constitution technique is adopted. The drilling degrees of freedom are added in the membrane part to improve membrane behavior. The proposed elements can be used for the analysis of both moderately thick and thin… More >