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 >

Edoardo Bucchignani¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 37-60, 2009, DOI:10.3970/fdmp.2009.005.037

Abstract This article describes an implicit method for the solution of time dependent Navier-Stokes equations written in terms of vorticity and velocity. The field equations are discretized using a finite volume technique over quadrilateral meshes.
The numerical code has been applied to the classical window cavity test, employing a fine stretched non-uniform grid, in order to provide an accurate steady solution for a high value of the Rayleigh number (10⁸). It has also been performed a simulation for a value of Rayleigh larger than the critical value, in order to show the capabilities of the proposed method to properly simulate… More >

A. Filali¹, L. Khezzar^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.3, pp. 307-329, 2013, DOI:10.3970/fdmp.2013.009.307

Abstract Numerical investigations of purely-elastic instabilities occurring in creeping flows are reported in planar cross-slot geometries with both sharp and round corners. The fluid is described by the upper-convected Maxwell model, and the governing equations are solved using the finite element technique based on a steady (non-iterative) direct solver implemented in the POLYFLOWcommercial software (version 14.0). Specifically, extensive simulations were carried out on different meshes, with and without the use of flow perturbations, for a wide range of rheological parameters. Such simulations show the onset of flow asymmetries above a critical Deborah number (De). The effect of rounding the corners is… More >

A.H. Ahadi¹, M.Z. Saghir¹

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.4, pp. 397-422, 2012, DOI:10.3970/fdmp.2012.008.397

Abstract The numerical simulations of a thermodiffusion experiment in atmospheric pressure binary mixtures of water and isopropanol subject to micro-vibrations at reduced gravity are presented. The vibrations are induced on board ISS and FOTON-M3 due to many different reasons like crew activity, spacecraft docking or operating other experiments, etc. The effects of micro-gravity vibration were investigated in detail on all of the mixture properties. The influences of different cavity sizes as well as different signs of Soret coefficients in the solvent were considered. In this paper, the thermodiffusion experiment was subjected to two different g-jitter vibrations on board ISS and FOTON-M3… More >

Marcello Lappa^{1, 2}

FDMP-Fluid Dynamics & Materials Processing, Vol.1, No.1, pp. 1-20, 2005, DOI:10.3970/fdmp.2005.001.001

Abstract Possible natural transport mechanisms in cubical and shallow cavities with different heating conditions (from below or from the side) are investigated by means of numerical solution of the non-linear model equations and multiprocessor computations. Attention is focused on a variety of three-dimensional steady effects that can arise in such configurations in the case of low-Pr liquids (silicon melt) even for relatively small values of the temperature gradient due to localized boundary effects and/or true instabilities of the flow. Such aspects are still poorly known or completely ignored owing to the fact that most of the existing experiments focused on the… More >

Sujoy Mukherjee¹, Ranjan Ganguli^1,2

CMC-Computers, Materials & Continua, Vol.19, No.2, pp. 105-134, 2010, DOI:10.3970/cmc.2010.019.105

Abstract In this study, variational principle is used for dynamic modeling of an Ionic Polymer Metal Composite (IPMC) flapping wing. The IPMC is an Electro-active Polymer (EAP) which is emerging as a useful smart material for `artificial muscle' applications. Dynamic characteristics of IPMC flapping wings having the same size as the actual wings of three different dragonfly species Aeshna Multicolor, Anax Parthenope Julius and Sympetrum Frequens are analyzed using numerical simulations. An unsteady aerodynamic model is used to obtain the aerodynamic forces. A comparative study of the performances of three IPMC flapping wings is conducted. Among the three species, it is… More >

Liviu Marin¹

CMC-Computers, Materials & Continua, Vol.17, No.3, pp. 233-274, 2010, DOI:10.3970/cmc.2010.017.233

Abstract We investigate two algorithms involving the relaxation of either the given boundary temperatures (Dirichlet data) or the prescribed normal heat fluxes (Neumann data) on the over-specified boundary in the case of the iterative algorithm of Kozlov91 applied to Cauchy problems for two-dimensional steady-state anisotropic heat conduction (the Laplace-Beltrami equation). The two mixed, well-posed and direct problems corresponding to every iteration of the numerical procedure are solved using the method of fundamental solutions (MFS), in conjunction with the Tikhonov regularization method. For each direct problem considered, the optimal value of the regularization parameter is chosen according to the generalized cross-validation (GCV)… More >

Zone-Ching Lin¹and Ren-Yuan Wang¹

CMC-Computers, Materials & Continua, Vol.16, No.3, pp. 247-272, 2010, DOI:10.3970/cmc.2010.016.247

Abstract The paper establishes a new three-dimensional quasi-steady molecular statics nanoscale abrasive cutting model to investigate the abrasive cutting behavior in the downpressing and abrasive cutting process of a workpiece in chemical mechanical polishing (CMP) process. The downpressing and abrasive cutting process is a continuous process. The abrasive cutting process is done after the single abrasive particle has downpressed and penetrated a workpiece to a certain depth of a workpiece. The paper analyzes the effects of the abrasive particles with different diameters on action force. It also analyzes the action force change of abrasive particles with different diameters on the projected… More >