Papers by Mohamed Meziane
L’industrie avicole est l’un des secteurs cles de l’economie nationale, dont le role pionnier dan... more L’industrie avicole est l’un des secteurs cles de l’economie nationale, dont le role pionnier dans la chaine alimentaire n’est plus a demontrer. Parmi les problemes que rencontre ce secteur, on peut citer un taux de mortalite eleve du souvent aux problemes de conditionnement. Les echangeurs air-sol permettent de realiser des economies substantielles en energie. Ils se caracterisent aussi par leur impact positif sur l’ambiance interne. Dans ce travail, nous presentons une modelisation et une etude parametrique d’un echangeur air-sol. Les resultats sont discutes suivant le parametre d’influence. Finalement, les gains energetiques sont estimes pour une etude de cas de l’installation d’un systeme dans la ville de Tanger.
In this paper, the damage at the interface zones between the fiber and the matrix of a composite ... more In this paper, the damage at the interface zones between the fiber and the matrix of a composite structure is studied. It is assumed that the composite is submitted to external forces that can damage the fiber–matrix interface zones. In this work, we use the boundary integral equation method to investigate the damage at the fiber–matrix interface. This method is compared to a micromechanical model elaborated via the finite element method. The compared numerical and theoretical results are in good agreement.
Deep drawing of sheet metal is one of the most important transformation’s process in which a shee... more Deep drawing of sheet metal is one of the most important transformation’s process in which a sheet metal blank is drawn into a forming die via a punch force. The conventional deep drawing of sheet metal techniques, known for their wide usage in several industry sectors, are experimental and expensive processes. Numerical simulation using Finite Element Methods (FEM) offers the ability of analyzing the feasibility of a process, allowing the benefit of saving time and considerably reducing costs by comparison with traditional methods. This virtual simulation requires the realization of the tools and their adjustment according to the resulting data till seizing a satisfactory adequacy of results. In this study, a Hill48 anisotropic yield criterion was adopted to express the mechanical material properties using ABAQUS/EXPLICIT software. A finite element model is developed for the 3D numerical simulation of sheet metal deep drawing process. Two aluminum alloys AA1050 and AA1100, were stu...
Journal of Applied Physics, 2013
The present paper is devoted to the 2D simulation of an Atmospheric Corona Discharge Reactor (ACD... more The present paper is devoted to the 2D simulation of an Atmospheric Corona Discharge Reactor (ACDR) involving 10 pins powered by a DC high voltage and positioned 7 mm above a grounded metallic plane. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The simulation involves the electro-dynamic, chemical kinetic, and neutral gas hydrodynamic phenomena that influence the kinetics of the chemical species transformation. Each discharge stage (including the primary and the secondary streamers development and the resulting thermal shock) lasts about one hundred nanoseconds while the post-discharge stages occurring between two successive discharge phases last one hundred microseconds. The ACDR is crossed by a lateral air flow including 400 ppm of NO. During the considered time scale of 10 ms, one hundred discharge/post-discharge cycles are simulated. The simulation involves the radical formation and thermal...
International Journal of Theoretical Physics, 2006
In a stationary case and for any potential, we solve the three-dimensional quantum Hamilton-Jacob... more In a stationary case and for any potential, we solve the three-dimensional quantum Hamilton-Jacobi equation in terms of the solutions of the corresponding Schrödinger equation. Then, in the case of separated variables, by requiring that the conjugate momentum be invariant under any linear transformation of the solutions of the Schrödinger equation used in the reduced action, we clearly identify the integration constants successively in one, two and three dimensions. In each of these cases, we analytically establish that the quantum Hamilton-Jacobi equation describes microstates not detected by the Schrödinger equation in the real wave function case.
International Journal of Theoretical Physics, 2006
In the one-dimensional periodic potential case, we formulate the condition of Bloch periodicity f... more In the one-dimensional periodic potential case, we formulate the condition of Bloch periodicity for the reduced action by using the relation between the wave function and the reduced action established in the context of the equivalence postulate of quantum mechanics. Then, without appealing to the wave function properties, we reproduce the well-known dispersion relations which predict the band structure for the energy spectrum in the Krönig-Penney model.
In a DC point-to-plane corona discharge reactor, the mono filamentary streamers cross the inter e... more In a DC point-to-plane corona discharge reactor, the mono filamentary streamers cross the inter electrode gap with a natural repetition frequency of some tens of kHz. The discharge phase (including the primary and the secondary streamers development) lasts only some hundred of nanoseconds while the post-discharge phases occurring between two successive discharge phases last some tens of microseconds. From the point of view of chemical activation, the discharge phases create radical and excited species located inside the very thin discharge filaments while during the post-discharge phases these radical and excited species induce a chemical kinetics that diffuse in a part of the reactor volume. From the point of view of hydrodynamics activation, the discharge phases induce thermal shock waves and the storage of vibrational energy which relaxes into thermal form only during the post-discharge phase. Furthermore, the glow corona discharges that persist during the post-discharge phases i...
International Journal of Renewable Energy Research, 2019
The interaction between Savonius vertical axis wind turbine clusters installed in far or close pr... more The interaction between Savonius vertical axis wind turbine clusters installed in far or close proximity can devalue or enhance the output power of single Savonius vertical axis wind turbines. In this paper, the effect of spatial distribution is studied for the development of efficient Savonius vertical axis wind turbine farms. Numerical simulations are performed for a single Savonius wind turbine, sets of two rotating turbines in three different configurations (aligned, parallel and oblique configurations), and clusters of three rotating turbines, using five separation distances of 0.25D, 0.5D, 1D, 1.5D and 2D, making a total of twenty-two test scenarios. The commercial CFD software Fluent 15.0 is used for the numerical study. The torque and power coefficient results of single Savonius turbine are compared and validated against experimental and numerical data based on the literature review. The results showed that there was a combined effect related to the inter-turbine distance...
The goal of this work is to simulate and improve the efficiency of an innovative multiple semicir... more The goal of this work is to simulate and improve the efficiency of an innovative multiple semicircular-bladed Savonius rotor, which is identified as belonging to the vertical axis wind turbine (VAWT) category. It is characterized as a low speed turbine that is simpler and cheaper to build than traditional turbines. This makes it appropriate for generating mechanical energy in lower wind speed regions, and it can be coupled with solar panels in urban agglomerations. The objective of this paper is to compare the aerodynamic characteristics and power efficiency of four different geometries (two-conventional and two-modified rotors) in order to estimate the most efficient design. The proposed Savonius design comprises multiple semicircular blades added to conventional twoand three-bladed Savonius configurations. The comparison of the efficiency in terms of the torque coefficient (CT) and power coefficient (CP) of the new system configurations with the conventional ones finds that the mu...
The European Physical Journal Applied Physics, 2011
The present paper shows for the first time in the literature a complete 2D simulation of the ozon... more The present paper shows for the first time in the literature a complete 2D simulation of the ozone production in a DC positive multi-tip to plane corona discharge reactor crossed by a dry air flow at atmospheric pressure. The simulation is undertaken until 1ms and involves tens successive discharge and post-discharge phases. The air flow is stressed by several monofilament corona discharges generated by a maximum of four anodic tips distributed along the reactor. The non stationary hydrodynamics model for reactive gas mixture is solved using the commercial FLUENT software. During each discharge phase, thermal and vibrational energies as well as densities of radical and metastable excited species are locally injected as source terms in the gas medium surrounding each tip. The chosen chemical model involves 10 neutral species reacting following 24 reactions. The obtained results allow us to follow the cartography of the temperature and the ozone production inside the corona reactor as a function of the number of high voltage anodic tips.
Engineering Failure Analysis
IEEE Transactions on Plasma Science, 2013
This paper is devoted to the simulation of the thermal shock and the induced pressure-waves expan... more This paper is devoted to the simulation of the thermal shock and the induced pressure-waves expansion, generated by a dc pin-to-plan corona discharge in the air at ambient temperatures and under atmospheric pressure. The positive dc voltage applied to the tip generates a monofilamentary streamer that crosses the gap from the tip toward the plan. The simulation models are based on the coupling of a 2-D dynamics streamer model with the hydrodynamics conservation equations of a compressible gas. The source term for the gas dynamics equations takes into account the fast-energy relaxation from excited molecules to the random thermal energy. The simulation shows that the streamers generate a thermal shock near the anodic tip, which induces high pressure gradients and finally the gas expansion. The thermal shock is located just in front of the anodic tip, where the injected energy density is the highest. After 0.3 µs, the mean gas temperature increases up to around 800 K in a small volume just in front of the anodic tip while the maximum temperature reaches 1200 K. In addition, two pressure waves, a spherical and a cylindrical one, are induced with a propagation velocity of 370 m s −1 i.e., close to the speed of sound in air.
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Papers by Mohamed Meziane