L. Belarche^1,2, B. Abourida¹, S. Smolen³

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.2, pp. 157-170, 2015, DOI:10.3970/fdmp.2015.011.157

Abstract Natural convection in a cubical cavity, discretely heated is studied numerically using a three-dimensional finite volume formulation. Two heating square portions are placed on the vertical wall of the enclosure, while the rest of the considered wall is adiabatic. The opposite vertical wall is maintained at a cold uniform temperature and the other walls are adiabatic. Effects of the heating sections dimensions ε (0.15 ≤ ε ≤ 0.35) and the Rayleigh number Ra (10³ ≤ Ra ≤ 10⁷) on the fluid flow and the heat transfer within the cavity are studied. The obtained results show that the flow More >

Z. Bouhssine¹, M. Faraji¹, M. Najam¹, M. El Alami^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.1, pp. 63-85, 2015, DOI:10.3970/fdmp.2015.011.063

Abstract The objective of this study is to optimize the thermal performance of a solar collector. The solar collector is coupled to a building slab with a PCM layer. A mathematical model for the thermal behavior of the studied system is developed using the enthalpy method. The model parameters are defined and the resulting equations are solved iteratively. Several simulations were carried out to optimize the proposed heating system. The results show that the inlet temperature fluctuations are less pronounced than those at the outlet. More >

Benjamin Lepers^a,*, Aditya Putranto^b,c, Martin Umminger^d, Guido Link^a, John Jelonnek^a

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-11, 2014, DOI:10.5098/hmt.5.13

Abstract The use of high power microwaves to perform explosive spalling of surface concrete is a promising technique with applications in the area of concrete facilities decommissioning. The mechanism that creates explosive spalling is an interactive process of the thermal stress from high temperature gradients and the pore pressure generated from the water vaporization. In order to better predict the total stress distribution, the temperature has to be calculated by including the effect of water vaporization and water transport through a porous medium. In this paper, a one dimensional model solving the heat and diffusion equation 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 More >

Imen Mejri^1,2, Ahmed Mahmoudi¹, Mohamed Ammar Abbassi¹, Ahmed Omri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 83-114, 2014, DOI:10.3970/fdmp.2014.010.083

Abstract This study examines natural convection in a square enclosure filled with a water-Al₂O₃ nanofluid and subjected to a magnetic field. The side walls of the cavity have spatially varying sinusoidal temperature distributions. The horizontal walls are adiabatic. A Lattice Boltzmann method (LBM) is applied to solve the governing equations for fluid velocity and temperature. The following parameters and related ranges are considered: Rayleigh number of the base fluid, from Ra=10³ to 10⁶, Hartmann number from Ha=0 to 90, phase deviation (γ =0, π/4, π/2, 3π/4 and π) and solid volume fraction of the nanoparticles between ø = 0 and More >

B. Mochnacki^*, Alicja Piasecka Belkhayat^†

Molecular & Cellular Biomechanics, Vol.10, No.3, pp. 233-244, 2013, DOI:10.3970/mcb.2013.010.233

Abstract Numerical analysis of heat transfer processes proceeding in a nonhomogeneous biological tissue domain is presented. In particular, the skin tissue domain subjected to an external heat source is considered. The problem is treated as an axially-symmetrical one (it results from the mathematical form of the function describing the external heat source). Thermophysical parameters of sub-domains (volumetric specific heat, thermal conductivity, perfusion coefficient etc.) are given as interval numbers. The problem discussed is solved using the interval finite difference method basing on the rules of directed interval arithmetic, this means that at the stage of FDM More >

Ewa Majchrzak^*

Molecular & Cellular Biomechanics, Vol.10, No.3, pp. 201-232, 2013, DOI:10.3970/mcb.2013.010.201

Abstract Heat transfer processes proceeding in the living organisms are described by the different mathematical models. In particular, the typical continuous model of bioheat transfer bases on the most popular Pennes equation, but the Cattaneo-Vernotte equation and the dual phase lag equation are also used. It should be pointed out that in parallel are also examined the vascular models, and then for the large blood vessels and tissue domain the energy equations are formulated separately. In the paper the different variants of the boundary element method as a tool of numerical solution of bioheat transfer problems More >

F. Freschi¹, L. Giaccone¹, M. Repetto¹

CMES-Computer Modeling in Engineering & Sciences, Vol.94, No.5, pp. 371-395, 2013, DOI:10.3970/cmes.2013.094.371

Abstract The study of induction heating systems from the electromagnetic point of view is still a challenging task for several reasons: the problem under analysis is strictly multiphysics because it involves the coupled electromagnetic and thermal phenomena; both coupled physics have nonlinear behavior; nonlinearities are of different kinds, both depending on the single phenomenon and on the coupling terms. The aim of the paper is to show that the cell method, based on the use of Tonti diagrams, can handle efficiently this kind of problems. The proposed magneto-thermal numerical procedure is firstly described in its theoretical More >

Adan Vega, Ernesto Escobar, Amaly Fong, Ninshu Ma, Hidekazu Murakawa

CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.3, pp. 197-210, 2013, DOI:10.3970/cmes.2013.090.197

Abstract This paper describes the effect of previous heating on inherent deformation by following heating, more specifically, the case of two heating lines applied parallel to each other. The novelty of the work lies in revealing the parallel effect and how, factors such as, for example, the heating condition and the plate geometry, influence the resulting inherent deformation of parallel heating. In addition, relationships to easily get these influences are provided. The results are suitable for a wide range of heating conditions and plate thickness. More >

Adan Vega, Alexandra Camaño, Amaly Fong, Sheriff Rashed, Hidekazu Murakawa

CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.2, pp. 147-163, 2013, DOI:10.3970/cmes.2013.090.147

Abstract The inherent deformation produced by two or more overlapped heating lines is not equal to that obtained when individual deformations are simply added. Thus, the effect of overlapping on inherent deformation, need to be clarified in order to achieve full understanding of the phenomenon of plate forming by line heating. In this paper, a 3D thermal-elasto-plastic FEA has been performed to study this problem in details. Using this FEA, the influence of previous heating on the inherent deformation of overlapped heating lines, considering various conditions, is clarified. From the results of this study, a method More >