FATIMAZOHRA Bakhti

REBHAOUI Abdel Aziz , MEDDAH Younes

Simulation numérique d’un capteur solaire plan muni d’un collecteur équipé d’un ruban torsadé

CHERHABIL Tarek , BELFAR Abdelbassit

ETUDE NUMERIQUE DE L'AMELIORATION DU TRANSFERT THERMIQUE DANS UN CAPTEUR SOLAIR CYLINDRO-PARABOLIQUE

BOURAHAL AHMED. , ABED NASSIF ABDELWAHID

ÉTUDE D`UN CALODUC UTILISÉ POUR LE REFROIDISSEMENT D`UN COMPOSANT ÉLECTRONIQUE.

ZIANE Bochra

ETUDE D’UN ECHANGEUR DE CHALEUR AIR-SOL UTILISE POUR LE RAFRAICHISSEMENT D’UN BATIMENT

KABOUYA Ilyas abou bakr

Simulation numérique d’un écoulement dans un échangeur de chaleur à surface raclée

ABIR AMROUNE

Etude numérique des performances thermique et hydrodynamique d’un écoulement dans un tube d'échangeur de chaleur équipé d'un ruban torsadé

HAMIDI YOUSSEF , R.ZEGHLACHE SAMIR

Simulation numérique de l’échange par naturelle thermique convection Des nanofluides dans une enceinte à paroi ondullée

zeguine belgassim , moualek imane

Simulation numerique de la convection mixte dans une nouvelle conception de dissipateur rotatif utilisé pour le refroidissement d'un CPU

Centrifugal fans are widely encountered in engineering practices, they are essential in the cement production process. The three dimensional, complex and turbulent flow in a centrifugal fan makes the prediction of the performance of the centrifugal fan and the examination of the flow field very difficult. Computational techniques have made a great progress, because of time and cost that may be involved in experimental analysis of the flow, computational fluid dynamics (CFD) is intensively used in many industrial purposes. Nevertheless, the agreement between the numerical results and real data is a subject of many researches, because the numerical result is very sensitive to the numerical method being used, the boundary conditions applied, mesh generation and turbulence model selection. To consider the interaction between the main three parts of the fan namely the inlet, impeller, and scroll, it is necessary to carry out a three-dimensional Numerical simulation of the flow field for the whole centrifugal fan. The impeller is the important part of the centrifugal fan and the aerodynamic design of the impeller blades affects the flow passage, thus improving the aerodynamic design of the blades results in improvements of fan performance and reduction of flow separation. The selection of turbulence model depends on the flow separation that can occur, particularly in the blade passage, thus in order to get a good numerical investigation of the performance of the fan and predict the internal flow field in the impeller, a Coordinate measuring machine (CMM) machine is used as a reverse engineering tool to extract the original impeller blade design of the induced Draft fan (FN-280) by using Geomatics software for point cloud processing.

Citation

Aissa AMOUR , FatimaZohra BAKHTI , noureddine MENASRI , , (2023), RETRO DESIGN OF IMPELLER BLADE OF THE INDUCED DRAFT FAN (FN-280) USING A COORDINATE MEASURING MACHINE (CMM), Journal Of Engineering And Applied Sciences, Vol:3, Issue:1, pages:19-26, Springer

The technological progress made in recent years has driven electronic apparatus to become not only more efficient and work faster but also considerably smaller in weight and size. Furthermore, the power densities of these devices have known an impressive increase. However, the challenge for the electronic industry is the lifetime device improvement by controlling the adequate removal of their excess heat. The use of more efficient cooling systems is, therefore, crucial in order to ensure durable device functionality. In this work, computational simulation was carried out to study the enhancement cooling process mixed convection of an electronic component (CPU mounted in a motherboard) using a new design of a heat exchanger by combining the heat sink (the finned surface) and the fan in a single component, this allows more heat to be moved faster and with less energy than a conventional cooler. Three radial heat sinks (HS18, HS24 and HS36) are considered depending on circumferential fin numbers (n = 18, 24 and 36). The effect of Reynolds number, heat flux and rotational velocity is investigated, and the optimum comprehensive performance was determined. The results reveal the cooling performance turns out to be better for heat sink with n = 36. The rotational velocity operates a significant effect on the temperature field only for values below than 900 rpm.We also found that the improvement in the Nusselt number and its percentage enhancement is intensified with increased rotational velocity and decreased with heat flux. A bigger Ω and ReΩ meant a more obvious heat transfer enhancement (NuΩ/Nu0) in the case of smaller Q, but (NuΩ/Nu0) decreased with increasing Q.

Citation

FatimaZohra BAKHTI , , (2022), Enhancement of the cooling by mixed convection of a CPU using a rotating heat sink: Numerical study, Part E: Journal of Process Mechanical Engineering, Vol:236, Issue:6, pages:1779-2278, SAGE Journals

The aim of this study is to examine by means of three-dimensional numerical simulations the thermal-fluid features in elliptical pin fin heat sink. The passive heat transfer enhancement technique is used to comprehend and control the cooling process. This passive methodology is based on pin fins arrangement, hydrodynamic and geometrical parameters. The present numerical results are confronted with experimental measurements in open literature which used one-dimensional model to explore the thermal field. A good agreement was found especially around the optimal fins dimensions. A parametric study has been carried out to deeply analyse the three-dimensional thermal-fluid fields of the heat sink for various key parameters range such the Reynolds number (Re = 50–250) and the aspect ratio (γ=H/d=5.1-9.18). Some new observations and results are obtained thanks to numerical simulations as tool of investigation. It is shown that the fins circumferential temperature is almost uniform. Furthermore, a better cooling is obtained when the Reynolds number increases mainly when the inlet velocity u0> 0.3m/s. The most suitable value of the aspect ratio is attained for γ=8.16, which ensure an optimal cooling process of the pins. A new global Nusselt number correlation was developed for engineering applications.

Citation

FatimaZohra BAKHTI , , (2021), Elliptical Pin Fin Heat Sink: Passive Cooling Control, International Journal of Heat and Technology, Vol:39, Issue:5, pages:1417-1429, international information and engineering technolgy association

This paper presents a numerical study on the mixed convection of nanofluids in heat sinks with perforated circular fins. Four different types of nanofluids are used as cooling fluids, which are TiO 2 , Al 2 O 3 and Cu dispersed in pure water as the base fluid. The selected volumetric concentration of nanofluids was chosen in the range (2–10)%. The Reynolds number has changed in the range of 100–400 to ensure that flow remains in the laminar regime and to have the Richardson number 1 ≤ Ri ≤ 22. To study the cooling performance of the heat sink, three-dimensional steady Navier Stokes and energy equations were discretized by the finite volume method using the power-law scheme and have been solved iteratively, using the SIMPLE algorithm. The results show that a significant improvement in heat transfer in the heat sink due to the suspension of nanoparticles in the base fluid compared to pure water, the improvement in heat transfer is intensified with increased Reynolds number and decrease in the volume fraction of nanoparticles. We also found that the low values of the average Nusselt number are obtained for the nanofluid TiO 2 , the average values for Al 2 O 3 and the highest values for Cu. It is important to note that a slight increase in friction factor and pumping power has been reported when nanofluid is used in the system.

Citation

FatimaZohra BAKHTI , Mohamed Si-Ameur, , (2019-05-20), A comparison of mixed convective heat transfer performance of nanofluids cooled heat sink with circular perforated pin fin, Applied Thermal Engineering, Vol:159, Issue:159, pages:113819, Elsevier

Ce polycopie du cours de transfert de chaleur est destiné aux étudiants Licence - Génie mécanique option génie des matériaux de l’université Med Boudiaf de M’sila, il est conçu pour permettre aux étudiants d’acquérir les mécanismes et concepts de base relatifs aux trois modes de transferts thermiques : conduction, convection, rayonnement. Selon les chapitres (en particulier la convection), certains prérequis en thermodynamique, mécanique des milieux continus, mécanique des fluides, calcul différentiel et/ou analyse numérique sont nécessaire. Dans le premier chapitre, ont été présentés les mécanismes physiques, les concepts et les lois de base régissant le transport de la chaleur par conduction, convection et rayonnement. Les chapitres qui suivent sont consacrés à l’étude de la conduction en régime permanent ou variable, selon une ou plusieurs directions ainsi que quelques méthodes de résolution analytiques (séparation des variables) et numériques (différences finis). Afin d’utiliser une même approche pour étudier la thermoconvection, une formulation générale des équations de transfert (masse, quantité de mouvement et énergie) a été présentée dans le cinquième chapitre, les deux chapitres qui suivent portent sur la convection externe et interne et la convection naturelle laminaire et turbulente. Le dernier chapitre concerne le transfert de chaleur par rayonnement. Les notions de corps noir et propriétés des surfaces radiatifs entre les surfaces sont introduits ainsi que quelques notions essentielles sur le rayonnement dans les milieux semi-transparents sont présentées à la fin de ce chapitre. Ce cours est enfin complété par une série d'annexes rassemblant les principales données thermo physiques nécessaires à la résolution d'un problème thermique.

Citation

FatimaZohraBAKHTI , ,(2019-01-02); TRANSFERT DE CHALEUR,Université of M'sila,

L’étude des processus de refroidissement suscite un très grand intérêt, plus particulièrement dans l’industrie électronique où la génération excessive de chaleur peut être la cause d’endommagement et de perte de matériel ou de système électronique utilisé. Améliorer le transfert convectif dans les dispositifs de refroidissement revient à intensifier l’échange thermique entre un fluide caloporteur et une surface chaude. On propose, dans ce travail, d'étudier le transfert de chaleur par convection mixte dans un dissipateur de chaleur à ailettes cylindriques perforées, les fluides caloporteurs sont l’eau et les nanofluides (eau+ TiO2 )et (eau+Cu) avec différentes fractions volumiques φ=2% - 10% et des nombres de Reynolds Re varie entre 100 et 400. Les simulations numériques ont été effectuées en utilisant le code FLUENT basé sur la méthode des volumes finis, les simulations numériques ont été réalisées pour étudier l’influence du nombre de Reynolds, la perforation dans les ailettes et le type de nanofluide sur le refroidissemnt du composant électronique. Les resultats numériques indiquent que l’ajout des perforations dans les ailettes et l’addition des nanoparticules(TiO2 et Cu) dans l’eau permet d’amélioer les performances de refroidissement du composant électronique.

Citation

FatimaZohra BAKHTI , ,(2018), Amélioration des performances de la convection mixte des nanofluides dans un dissipateur de chaleur à ailettes cylindriques perforées,International seminar in Industrial Engineering and Applied Mathematics,Skikda-Algérie

This present numerical study investigates on mixed convection of nanofluids in heat sink with circular perforated pin fins. Four different kinds of nanofluids are used as a cooling fluid which are TiO2, Al2O3 and Cu dispersed in pure water as a base fluid. The volumetric concentration of selected nanofluids has been chosen in range (2-10)%. The Reynolds number changed in the range of 100–400 to ensure that, the flow remains in the laminar regime and to have Richardson number 1≤Ri≤22. To investigate the cooling performance of the heat sink, three-dimensional steady Navier Stokes and energy equations were discretized by finit volume method using the power-law scheme and have been solved iteratively, using the SIMPLE algorithm. The results show that a significant enhancement of heat transfer in the heat sink due to suspension of nanoparticles in the base fluid in comparison with pure water, enhancement of heat transfer is intensified with increasing Reynolds number and decreasing volume fraction of nanoparticles. We also found that the low values of the average Nusselt number are obtained in the case of the nano fluid TiO2, the average values for Al2O3 and the largest values for Cu.

Citation

FatimaZohra BAKHTI , ,(2018), A comparison of mixed convective heat transfer performance of nanofluids cooled heat sink with circular perforated pin fin,4 International Conference on Advances In Mechanical Engineering IStanbul 2018,Instanbul -Turkey