Shueei-Muh Lin ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.72, No.1, pp. 17-36, 2011, DOI:10.3970/cmes.2011.072.017

Abstract In this study, examine the in-plane vibration of a robot arm picking and placing a mass along arbitrary curved tracking. This mathematical model is established. It is a moving mass problem. Due to the effect of movement along arbitrary curved tracking, the corresponding differential equation is nonlinear with the time-dependent coefficients and non-homogenous boundary conditions. So far, a few literatures devoted to investigate this system due to its complexity. The solution method procedure for this system is presented. It integrates several methods as the transform of variable, the subsection method, the mode superposition method, and the Green function method. Meanwhile,… More >

Masato Saitoh¹

CMES-Computer Modeling in Engineering & Sciences, Vol.67, No.3, pp. 211-238, 2010, DOI:10.3970/cmes.2010.067.211

Abstract This paper describes the transformation of impedance functions in general structural systems with non-classical damping into a one-dimensional spring-dashpot system (1DSD). A transformation procedure based on complex modal analysis is proposed, where the impedance function is transformed into a 1DSD comprising units arranged in series. Each unit is a parallel system composed of a spring, a dashpot, and a unit having a spring and a dashpot arranged in series. Three application examples are presented to verify the applicability of the proposed procedure and the accuracy of the 1DSDs. The results indicate that the 1DSDs accurately simulate the impedance functions for… More >

M.Galli , M.L.Oyen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.48, No.3, pp. 241-270, 2009, DOI:10.3970/cmes.2009.048.241

Abstract A novel approach is presented for the identification of constitutive parameters of linear poroelastic materials from indentation tests. Load-controlled spherical indentation with a ramp-hold creep profile is considered. The identification approach is based on the normalization of the time-displacement indentation response, in analogy to the well-known one-dimensional consolidation problem. The identification algorithm consists of two nested optimization routines, one in the time-displacement domain and the other in a normalized domain. The procedure is validated by identifying poroelastic parameters from the displacement-time outputs of finite element simulations; the new identification scheme proves both quantitatively reliable and fast. The procedure is also… More >

E. Ferretti¹, E. Casadio, A. Di Leo¹

CMES-Computer Modeling in Engineering & Sciences, Vol.30, No.3, pp. 163-190, 2008, DOI:10.3970/cmes.2008.030.163

Abstract In this study, the Cell Method (CM) is applied in order to investigate the failure mechanisms of masonry walls under shear force. The direction of propagation is computed step-wise by the code, and the domain is updated by means of a propagation technique of intra-element nodal relaxation with re-meshing. The crack extension condition is studied in the Mohr/Coulomb plane, using the criterion of Leon. The main advantage of using the CM for numerical analyses of masonry is that the mortar, the bricks and the interfaces between mortar and bricks can be modeled without any need to use homogenization techniques, simply… More >

N.Kringos¹, A.Scarpas¹, A.P.S. Selvadurai²

CMES-Computer Modeling in Engineering & Sciences, Vol.28, No.3, pp. 147-160, 2008, DOI:10.3970/cmes.2008.028.147

Abstract This paper presents a numerical approach for the modeling of water flow induced mastic erosion from a permeable asphalt mix and is part of an ongoing effort to model moisture-induced damage in asphalt mixes. Due to the complex composite structure of asphalt mixtures, moisture can infiltrate in various ways into the components and have an adverse effect on its mechanical performance. Depending on the gradation of the asphalt aggregates and the mixing procedure, asphalt structures with a variable permeability may result. Open-graded asphalt mixes are designed with a high interconnected air void content to serve as a drainage layer on… More >

Cherfi Ryad^1,*, Sadaoui Djamel¹, Sahi Adel¹, Mouloud Smail¹

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.2, pp. 153-169, 2019, DOI:10.32604/fdmp.2019.04294

Abstract The present work relates to a numerical investigation of double diffusive mixed convection around a horizontal annulus with a finned inner cylinder. The solutal and thermal buoyancy forces are sustained by maintaining the inner and outer cylinders at uniform temperatures and concentrations. Buoyancy effects are also considered, with the Boussinesq approximation. The forced convection effect is induced by the outer cylinder rotating with an angular velocity (ω) in an anti-clockwise direction. The studies are made for various combinations of dimensionless numbers; buoyancy ratio number (N), Lewis number (Le), Richardson number (Ri) and Grashof number (Gr). The isotherms, isoconcentrations and streamlines… More >

Qiping Chen¹, Yu Liu¹, Liping Zeng¹, Qiang Xiao¹, Conghui Zhou¹, Sheng Kang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.4, pp. 281-291, 2018, DOI:10.32604/fdmp.2018.03721

Abstract The brake-by-wire system requirement is promoted owing to the development of green energy vehicle, and the brake pressure control method is needed. A control method for the master cylinder hydraulic pressure based on the sliding mode control approach is proposed to provide the Electro-Hydraulic Brake system (EHB) of electric vehicles with superior system performances. An assessment is carried out about the complex nonlinear characteristics and sensitivity to the external environment of these systems, which include illustrating the working principle of the EHB system, establishing the dynamic models of the key components of the EHB system. The sliding mode control method… More >

Nouri Sabrina^1,*, Abderrahmane Ghezal¹, Said Abboudi², Pierre Spiteri³

FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.2, pp. 121-135, 2018, DOI: 10.3970/fdmp.2018.02045

Abstract This paper deals with the numerical study of heat and mass transfer occurring in a cavity filled with a low Prandtl number liquid. The model includes the momentum, energy and mass balance equations. These equations are discretized by a finite volume technique and solved in the framework of a custom SIMPLER method developed in FORTRAN. The effect of the problem characteristic parameters, namely the Lewis and Prandtl numbers, on the instability of the flow and related solute distribution is studied for positive and negative thermal and solutal buoyancy forces ratio. Nusselt and Sherwood numbers are derived for values of the… More >

M. Ihdene¹, T. Ben Malek², S. Aberkane³, M. Mouderes⁴, P. Spiterri⁵, A. Ghezal²

FDMP-Fluid Dynamics & Materials Processing, Vol.13, No.2, pp. 85-105, 2017, DOI:10.3970/fdmp.2017.013.085

Abstract We consider an ascending laminar air flow in a vertical channel formed by two parallel flat plates wetted by a thin water film and under different temperature and concentration conditions. The study includes a numerical finite volume method for the treatment of the double diffusion problem, where the analytical solution is given to the thermal diffusion. The analytical study showed that the reversed flow is observed only under some wall temperature conditions and also for certain values of Re/Gr. The reversed flow is also strongly dependent on the aspect ratio A₂, which is based on the cross section of the… More >

Gnaneswara Reddy Machireddy¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.4, pp. 417-442, 2014, DOI:10.3970/fdmp.2014.010.417

Abstract This study deals with the investigation of the effects exerted by heat radiation and a first-order chemical reaction on the magnetohydrodynamics boundary layer slip flow which is established past a vertical permeable surface embedded in a porous medium (with uniform heat and mass flux). The heat equation includes the relevant terms, i.e. the viscous dissipation, radiative heat flux, Ohmic dissipation, and absorption of radiation. The mass transfer equation takes into account the effects related to the chemically reactive species. A classical model for optically thin media is used for studying the effect of radiation. The resulting non-linear coupled partial differential… More >