Browsing by Author "Halouane, Yacine"

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Analysis of a reactive porous separation effects on depollution and indoor air quality: Application of LBM-MRT to heat and mass transfers
(Elsevier, 2024) Arab, Assia; Himrane, Nabil; Hireche, Zouhira; Halouane, Yacine; Bennacer, Rachid; Ameziani, Djamel Eddine
The reduction of energy demand and the indoor air quality associated with energy demand are the main goals of thermal buildings. This work is devoted to the study of the effect of a reactive porous separation on the ventilation (cooling) and depollution capacity in a rectangular room ventilated by air displacement. The model is considered as a cavity heated on its right verticle wall and thermally isolated by the other three walls. A porous separation divides the room into two compartments. The system of equations was solved using the Lattice Boltzmann method with multiple relaxation times. The extended Darcy Brinkman-Forchheimer model was used to simulate the porous material. An additional linear term is added to the standard transport equations (material diffusion) to account for reaction effects, this term was derived from Arrhenius' law. Over a wide range of Richardson and Darcy numbers, the results of the computations show the influence of these parameters on the flow structure, making it possible to categorize the different convection phenomena (natural, forced and mixed). The most important point to note is that the addition of reaction (fixing reaction) improves indoor air quality and can achieve a 55 % reduction in air renewal time, thus saving on energy costs. However, this reactif effect has no influence on the thermal efficiency of the proposed model.
Contribution à l'étude de l'interaction d'un jet axisymétrique avec une cavité cylindrique chauffée
(2014) Halouane, Yacine
Le présent travail est une contribution à l'étude d'une interaction symétrique d'un jet axisymétrique turbulent, issu d'une longue conduite à l'intérieur d'une cavité cylindrique chauffée à fond fermé. L'interaction jet-cavité est analysée numériquement à l'aide de deux modèles statistiques de turbulence de fermeture en un point RANS: - Le modèle k- réalisable du premier ordre - Le modèle des tensions de Reynolds (Reynolds Stress Model-RSM) du second ordre. La résolution numérique des équations du mouvement et celle de l'énergie sont effectuées par le code CFD ANSYS (Fluent14) basé sur une méthode des volumes finis et qui nécessite l'usage du code Gambit 6.3 pour générer la géométrie, le maillage et les conditions aux limites du problème. Les champs dynamique et thermique ont été investigués pour différent distances d'impact du jet avec le fond de la cavité, de 2d à 12d (d étant le diamètre du jet) et pour une gamme du nombre de Reynolds Re variant de 2 104 à 5 104 correspondant à une turbulence pleinement développée. Une validation a été effectuée avec des travaux expérimentaux disponibles dans la littérature. Les résultats obtenus ont permis de confirmer les observations suivantes : " L'écoulement dans la cavité se compose de trois zones principales : a. Une zone de jet libre. b. Une zone d'interaction du jet principale avec l'écoulement de retour. c. Une zone stagnante située au fond de la cavité qui forme un tourbillon toroïdale. " L'interaction d'un jet rond avec une cavité cylindrique génère un écoulement stable (non oscillatoire) parfaitement symétrique. " Le chauffage n'a pas une influence sur la structure globale d'écoulement (Problème de convection forcée). " Cette étude nous a permis de proposer des corrélations en fonction du nombre de Reynolds Re et de la distance d'impact Lf, pour nombre du Nusselt au point d'arrêté Nu0 (Nu0=f(Re,Lf)) et le nombre de Nusselt moyen Nuavr (Nuavr=f(Re,Lf)
Flow and heat transfer of air round jet flowing inside a hot cylindrical cavity
(2014) Halouane, Yacine; Mataoui, Amina
Heat transfer prediction of a jet impinging a cylindrical deadlock area
(American Society of Mechanical Engineers (ASME), 2014) Halouane, Yacine; Mataoui, Amina; Iachachene, Farida
Heat transfer related to a self-sustained oscillating plane jet flowing inside a rectangular cavity
(IEEE, 2014) Iachachene, Farida; Matoui, A.; Halouane, Yacine
LBM-MRT study of a reactive porous separation on thermal and depollution efficiency in a ventilated room
(Elsevier Ltd, 2024) Arab, Assia; Himrane, Nabil; Ameziani, Djamel Eddine; Hireche, Zouhira; Halouane, Yacine; Magherbi, Mourad
This work investigates a mixed laminar thermosolutal convection phenomenon in a cavity ventilated by air displacement, equipped with a reactive porous separation of variable height inside. The Lattice Boltzmann method with multiple relaxation times (LBM-MRT) was adopted for the mathematical resolution. The extended Darcy Brinkman-Forchheimer model was used to simulate the porous material. The objective of this work is to improve the energy efficiency of ventilation systems and optimize indoor air quality. The main novelty of this research lies in the introduction of a complement to ventilation, in the form of a fixation reaction, making it possible to develop a physical model based on both the elimination and fixation of pollutants. The model represents a rectangular cavity with heating one of its vertical walls, while the other walls are adiabatic. The geometric and flow parameters examined are the height of the porous separation (Hp), its permeability (Darcy number), the fixing reaction rate (Ak) and the Reynolds Reas well as the Rayleigh Ra numbers. The most notable result concerns the estimated improvement of around 52% in thermal efficiency. This occurs in the case of a high Darcy number (Da=10−2), a height of 0.3, a moderate flow rate (Rec=5×102) and maximum thermal heating (Ra=106). This improvement is compared to case with a low Darcy value (Da=10−6). In the same scenario, the thermal efficiency reaches its peak at a height of 0.9. The results show that the impact of the fixation reaction and the height Hp is most noticeable at low permeabilities (low Da), as the porous separation acts as a solid wall. As a result, an increase in Hp leads to an expansion of the dead zone in the second compartment, creating a zone that is both polluted and thermally uncomfortable.
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, Yacine
Turbulent heat transfer for impinging jet flowing inside a cylindrical hot cavity
(Serbian Society of Heat Transfer Engineers, 2015) Halouane, Yacine; Mataoui, Amina; Iachachene, Farida
Convective 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)
Turbulent jet impinging a cylindrical hot cavity
(Springer, 2014) Halouane, Yacine; Mataoui, Amina; Iachachene, Farida