E. Viola¹, F. Tornabene²

Structural Durability & Health Monitoring, Vol.1, No.2, pp. 155-170, 2005, DOI:10.3970/sdhm.2005.001.155

Abstract In this paper, generalized differential quadrature techniques are applied to the computation of the in-plane free vibrations of thin and thick non-uniform circular arches in undamaged and damaged configurations, when various boundary conditions are considered. Structural damage is represented by one crack in different positions and with various damage levels. The crack present in a structural member can be considered as a local stiffness reduction at the fracturing section, which changes the dynamic behaviour of the structure. Much effort has been devoted to dealing with in-plane free vibration analysis of circular arches, but only a… More >

U. Andreaus^1,3, R.C. Batra², M. Porfiri^{2, 3}

CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.2, pp. 111-132, 2005, DOI:10.3970/cmes.2005.009.111

Abstract Structural health monitoring techniques based on vibration data have received increasing attention in recent years. Since the measured modal characteristics and the transient motion of a beam exhibit low sensitivity to damage, numerical techniques for accurately computing vibration characteristics are needed. Here we use a Meshless Local Petrov-Galerkin (MLPG) method to analyze vibrations of a beam with multiple cracks. The trial and the test functions are constructed using the Generalized Moving Least Squares (GMLS) approximation. The smoothness of the GMLS basis functions requires the use of special techniques to account for the slope discontinuities at More >

Marcello Lappa¹

FDMP-Fluid Dynamics & Materials Processing, Vol.1, No.2, pp. 171-188, 2005, DOI:10.3970/fdmp.2005.001.171

Abstract The paper presents a comparative and critical analysis of some theoretical/experimental/numerical arguments concerning the possible stabilization of the surface-tension-driven (Marangoni) flow in the Floating Zone technique and in various related fluid-dynamic models. It is conceived as a natural extension of the focused overview published in Cryst. Res. Tech. 40(6), 531, (2005) where much room was devoted to discuss the intrinsic physical mechanisms responsible for three-dimensional and oscillatory flows in a variety of technological processes. Here, a significant effort is provided to illustrate the genesis of possible control strategies (many of which are still in a More >

L. F. Qian^1,2, R. C. Batra³, L. M. Chen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.5, pp. 519-534, 2003, DOI:10.3970/cmes.2003.004.519

Abstract We use a meshless local Petrov-Galerkin (MLPG) method to analyze three-dimensional infinitesimal elastodynamic deformations of a homogeneous rectangular plate subjected to different edge conditions. We employ a higher-order plate theory in which both transverse shear and transverse normal deformations are considered. Natural frequencies and the transient response to external loads have been computed for isotropic and orthotropic plates. Computed results are found to agree with those obtained from the analysis of the 3-dimensional problem either analytically or by the finite element method. More >