Publications Scientifiques
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Item Optimised heat exchange in a magnetised nanofluid-filled cavity using hybrid deep neural network and metaheuristic algorithms(Taylor and Francis Ltd., 2025) Benderradji, Razik; Laouissi, Aissa; Karmi, Yacine; Abderazek, Hammoudi; Chetbani, Yazid; Belaadi, Ahmed; Mukalazi, Herbert; Ghernaout, Djamel; Chamkha, AliThis study presents a comprehensive numerical investigation into steady-state mixed convection heat transfer within a square ventilated cavity containing a centrally positioned isothermal cold cylinder. The objective is to assess the combined effects of nanofluids and magnetic fields on thermal performance. The working fluids considered include pure water and water-based nanofluids enhanced with copper (Cu) and aluminium oxide (Al2O3) nanoparticles. Simulations were conducted across a range of Richardson numbers (0.1 < Ri < 100), Hartmann numbers (0 < Ha < 100), and nanoparticle volume fractions (0% < φ < 8%), using the finite volume method and the SIMPLER algorithm. Distinct from prior studies, this work bridges two gaps: (i) quantifying how high magnetic fields (Ha > 50) diminish nanoparticle-enhanced heat transfer and (ii) integrating artificial intelligence not only for prediction but also optimisation. Specifically, three machine learning models Decision Tree (DT), K-Nearest Neighbors (KNN), and a Deep Neural Network optimised via Genetic Algorithm (DNN-GA) were trained on 160 high-fidelity simulation datasets to estimate the average Nusselt number. Results demonstrated the DNN-GA’s superior accuracy (R² = 0.999, RMSE = 0.021) over DT (R² = 0.978) and KNN (R² = 0.921). Furthermore, five metaheuristic algorithms Queuing Search Algorithm (QSA), Barnacles Mating Optimiser (BMO), Search and Rescue (SAR), Gradient-Based Optimiser (GBO), and Manta Ray Foraging Optimisation (MRFO) were applied to maximise heat transfer. Optimisation identified Cu nanoparticles at Ri = 109.7, Ha = 9.0, and φ = 6% as optimal (Nu = 34.95), validated experimentally with 0.89% error. The findings confirm that increasing Ri and Ha enhances heat transfer efficiency (by 12–18%), while nanoparticle contribution declines (to 3–5%) at higher Ha. This work offers a dual contribution: advancing understanding of MHD nanofluid interactions in ventilated cavities and demonstrating a robust AI-driven framework for thermal system design. Highlights: Analysis of mixed convection in a ventilated cavity using Cu-water and Al2O3-water nanofluids under varying Richardson and Hartmann numbers. Examination of magnetic field impacts on heat transfer and nanofluid flow. Comparative study of Al2O3 and Cu nanoparticles on heat transfer enhancement. Provides valuable insights into the combined effects of nanoparticles, magnetic fields, and convection parameters. Machine learning models are very useful for predicting the Nusselt number. Metaheuristics algorithms are highly effective in optimising heat transfer processesItem Numerical simulation and experimental analysis of magneto-mechanical behavior of anti-seismic active sandwich structure(Extrica, 2019) Zerrouni, Nassim; Aguib, Salah; Grine, Ali; Chikh, NoureddineThis work focuses on the quasi-static behavior study for simply supported sandwich beams with aluminum faces and magnetorheological elastomer core subjected to three points bending subjected to a magneto-mechanical loading by numerical and experimental investigations. The mechanical properties of the magnetorheological elastomer core are measured experimentally and the mechanical behavior of the MRE was identified by the generalized Maxwell rheological model. Depending upon the adjustable properties of the beam, energy dissipation is by core shear. A systematic series of experiments and finite elements simulations have been performed in order to assess the static behavior of the beam. The results obtained show a significant influence of the magnetic field intensity on the flexural displacement of the beam.Item Analysis of buckling stability behavior of hybrid plate using Ritz approach and numerical simulation(Elsevier, 2021) Aguib, Salah; Chikh, N.; Kobzili, L.; Djedid, T.; Nour, A.; Meloussi, MounirIn this article, we studied the instability phenomenon of plate buckling made of steel (E36-S355), and magnetorheological elastomer subject to compression loading. The study of the magnetic field intensity influence on the buckling instability of compressed hybrid plates is done by a mathematical development using the Ritz approach and by a numerical simulation under the Abaqus software. The obtained results show clearly that we can control the instabilities of the adaptive smart plate’s behavior by the magnetic field, and the orientation angle of pseudo-fibers formed by the iron particles; depending on the variation of the angle direction of the magnetic fieldItem Measurements and identification of smart magnetomechanical elastomer composite materials properties in shear mode(Institute of Physics Publishing, 2019) Nedjar, Ali; Aguib, Salah; Djedid, Toufik; Nour, Abdelkader; Meloussi, MounirMagnetorheological elastomer composite materials (MRE) are a new class of intelligent active materials composed of ferromagnetic particles, of micrometric size, dispersed in a silicone elastomer matrix, which exhibit variable stiffness and damping properties which are modifiable under the application of an external magnetic field. Currently, these devices are primarily used in automotive and building applications, but they can easily be adapted to meet the requirements of aerospace applications. The development process and experimental characterization needed to evaluate the active control performance of this material have been made. This is done by characterizing the mechanical properties as a function of the magnetic field, as a function of the excitation frequency and as a function of the different percentage of ferromagnetic particles loading. An example of application of this material in aeronautics is also presentedItem Development and design of helmholtz coil for NBTI degradation studies(IEEE, 2017) Merah, Sidi Mohammed; Nadji, BouchraLaboratory of Electrification of Industrials Enterprises (LREEI) of boumerdes and CDTA have developed an in-house Helmholtz coil. It will be used as a source of external magnetic field for studying the Negative Bias Temperature Instability (NBTI) degradation mechanisms that can influence Metal Oxide Semiconductor (MOS) devices. This paper describes the different phases of design and construction of a Helmholtz coil controlled by a computer. Structure geometry, number of turns in winding and power supply calculations were done. The two windings are connected in series and the magnetic field was measured at different points. The results obtained were satisfactory. The magnetic field is uniform over an approximate length of 22 cmItem Hydrodynamic instabilities in swirling flow under axial magnetic field(ELSEVIER, 2021) Laouari, A.; Mahfoud, B.; Bessaïh, R.; Hadjadj, A.The present paper investigates numerically the hydrodynamic instabilities occurring in a cylindrical container filled with a conducting viscous fluid and submitted to an axial magnetic field. The axisymmetric swirling flow produced by rotation of the bottom disk, in which a vortex breakdown bubble occurred on the axis of symmetry. This flow structure represents one of the most important instabilities. The governing Navier–Stokes and potential equations are solved by using the finite-volume method. For both steady-state and oscillatory regimes, various combinations of the top, bottom, and side walls conductivity are considered. The effects of the magnetic field and wall electrical conductivities on the position of vortex breakdown and his disappearance is developed. The results obtained showed that the vortex breakdown is suppressed beyond the magnitude of the magnetic field exceeds a critical value. The stability diagram (Ha–Re) corresponding to the vortex breakdown disappearance for electrically conducting and insulating walls is obtained.Item Vibration control of a hydrostatic bearing using magnetorheological elastomer shell bearing(JVE International, 2018) Chikh, Noureddine; Aguib, Salah; Djedid, Toufik; Nour, Abdelkader; Tawfiq, ImadIn rotating machines, random movements or sliding movements of the rotor in its housing can produce undesirable phenomena for some parts. To solve this problem, a new hydrostatic bearing with an intelligent magnetorheological elastomer sell bearing has been designed to control the undesirable vibrations of rigid rotors. The different effects of the influence parameters on the vibratory behavior of the sell bearing are calculated numerically using Abaqus software, and the results found are encouragingItem Numerical study of the effect of transverse magnetic field on cylindrical and hemispherical CZ crystal growth of silicon(Thomson Scientific, 2010) Mokhtari, Faiza; Bouabdallah, Ahcene; Merah, AbdelkrimItem Numerical investigation of magnetic field effect on pressure in cylindrical and hemispherical silicon CZ crystal growth(Wiley, 2012) Mokhtari, Faiza; Bouabdallah, Ahcene; Merah, Abdelkrim; Oualli, HamidItem Symmetry breaking in electromagnetic spherical Cz crystal growth with rotating crystal and crucible(American Scientific Publishers, 2013) Mokhtari, Faiza; Bouabdallah, A.; Merah, Abdelkrim