Publications Internationales
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Item Numerical analysis of gray gas radiation effects on heat and mass transfer in an annular cavity(Serbian Society of Heat Transfer Engineers, 2024) Boussandel, Abdelaziz; Laouar-Meftah, Siham; Retiel, NoureddineThis study deals with a numerical investigation of coupled double diffusive natural-convection with thermal radiation in an annular cavity containing a gray gas mixture. The black vertical cylindrical walls are maintained at different temperatures and concentrations to create cooperating flows. The finite volume method (using the SIMPLER algorithm) is used to solve the governing equations and the discrete ordinate method (with S8 quadrature) to treat the radiative aspect of the problem. A parametric study illustrating the influence of the optical thickness and the ratio of buoyancy forces, on the flow field and heat and mass transfer for Reyleigh number equal to 5 ∙ 106 and aspect ratio equal to 1, is performed. The numerical results show that gas radiation modifies the flow structure and the distribution of temperature and concentration in the cavity. The effect of permutation of boundary conditions, between the vertical walls, on heat and mass transfer is also considered. The thermal radiation reduces the total heat transfer in the annular space regardless of the configuration of the boundary conditionsItem Towards numerical simulation tool of motion solid particles in fluid flow(International Society of Multiphysics, 2021) Zouaoui, S.; Djebouri, H.; Ferhat, B.; Mohammedi, K.We present here a numerical method to compute the motion of rigid particles in fluid flow with a non-elastic impact law. Many methods have been proposed recently and different strategies have been used to compute such flows. Our motivation is the handling of the non-overlapping constraint in fluid-particle direct simulations. Each particle is treated individually and the Navier-Stokes equations are solved for the moving fluid by Fluent code which is based on the Finite Volume Method. The contact-handling algorithm, which is implemented in a research C ++, is based on the projection of the velocity field of the rigid particles over the velocity field of the fluid flow. The method consists of imposing a constraint on the velocity field of the particles, as a guarantee that at each time step the calculated particle velocity field belongs to an eligible velocity field of the fluid. In this case study, an Uzawa algorithm has been appliedItem Magnetohydrodynamic effect on flow structures between coaxial cylinders heated from below(American Institute of Aeronautics and Astronautics Inc., 2020) Mahfoud, B.; Benhacine, H.; Laouari, A.; Bendjaghlouli, A.Numerical simulationswereperformedinordertostudycombinedforcedandnaturalconvectionflowbetweentwo coaxial vertical cylinders under an axial magnetic field. The effects of the axial magnetic field and six annular gaps on flow structures and heat transfer were assessed. The governing Navier-Stokes, energy, and potential equations are solved by using the finite volume method. The three-dimensional symmetry breaking of the basic state appears as the annular gaps become larger. Asymmetric m = 1 and 2 azimuthal modes are observed. Finally, our results show that the magnetic field controls both the heat transfer and the transition to asymmetry flow. © 2019 by the American Institute of Aeronautics and Astronautics, Inc.Item Turbulent heat transfer for impinging jet flowing inside a cylindrical hot cavity(Serbian Society of Heat Transfer Engineers, 2015) Halouane, Yacine; Mataoui, Amina; Iachachene, FaridaConvective heat transfer from an isothermal hot cylindrical cavity due to a turbulent round jet impingement is investigated numerically. Three-dimensional turbulent flow is considered in this work. The Reynolds stress second order turbulence model with wall standard treatment is used for the turbulence predictions the problem parameters are the jet exit Reynolds number, ranging from 2·104 to 105 and the normalized impinging distance to the cavity bottom and the jet exit Lf, ranging from 4 to 35. The computed flow patterns and isotherms for various combinations of these parameters are analyzed in order to understand the effect of the cavity confinement on the heat transfer phenomena. The flow in the cavity is divided into three parts, the area of free jet, and the area of the jet interaction with the reverse flow and the semi-quiescent flow in the region of the cavity bottom. The distribution of the local and mean Nusselt numbers along the cavity walls for above combinations of the flow parameters are detailed. Results are compared against to corresponding cases for impinging jet on a plate for the case of the bottom wall. The analysis reveals that the average Nusselt number increases considerably with the jet exit Reynolds number. Finally, it was found that the average Nusselt number at the stagnation point could be correlated by a relationship in the form Nu = f(Lf, Re)Item Numerical investigations on heat transfer of self-sustained oscillation of a turbulent jet flow inside a cavity(American Society of Mechanical Engineers (ASME), 2015) Iachachene, Farida; Mataou, Amina; Halouane, YacineItem Laminar natural convection flow in cylindrical cavity application to the storage of LNG(Elsevier, 2010) Khelifi-Touhami, M. S.; Benbrik, Abderahmane; Lemonnier, D.; Blay, D.The numerical simulation of laminar natural convection in a vertical cylindrical cavity is proposed. The cavity is insulated at the bottom, laterally heated at a uniform heat flux and cooled by a non uniform evaporative heat flux at the top surface obeying the Hashemi–Wesson's law. The equations of mass conservation, momentum and energy are resolved with finite-volume method in fully implicit form. The influence of the characteristic parameters (103≤Ra≤105, Pr=2, 1/3≤Al≤1) on the thermal and dynamic behavior at steady state is analysed and discussed. In particular, the study describes the solutions at Ra=105 and Pr=2 for various aspect ratios. The evaporative heat flux is computed for all the parameters and it is found that its maximum is localized near the lateral wall whereas its minimum is at the free surface center