ABDELKRIM Bouras

AMROUNE Manal

Installation de kit de pompage immergé avec panneau solaire

LATTOUI Kheir eddine , REFICE Abdelghafar

Etude numérique de la convection naturelle avec nano-fluides, entre un transformateur à l’intérieur et un réservoir fermé à l’extérieur

Lograb Sadam , Saidi Malika

Etude numérique de la convection naturelle des nanofluides dans un anneau horizontal entre un cylindre interne triangulaire et un cylindre extérieur elliptique froid.

SALAMANI Fatima Zohra , ROBEI Hafida

Etude numérique de la convection naturelle des anneau horizontal entre nano fluides dans un un cylindre interne elliptique chauffé et un cylindre extérieur carrée froid.

Cherhabil Zakaria , Mouafak Riyadh

Etude de l’influence des paramètres internes sur un capteur solaire

DEBKA Siham , DEBKA Esmahane

Étude numérique du transfert de chaleur par convection naturelle des nano fluides dans un espace annulaire, situé entre deux cylindres un cylindre extérieur elliptique et un cylindre intérieur carrée.

Bouchakour boubekeur , Bouchareb Kouider

Simulation numérique de la convection naturelle double diffusion entre deux cylindres elliptiques influence de l'inclinaison

CHERIGUI AMAL , THARAFI AHLAM

Estimation de rayonnement solaire en M'sila cas d'un ciel clair

Kihoul Khadidja , Bounab Lynda

Estimation du Rayonnement Solaire en Station d’Ain El Melh Cas d’un Ciel Clair

KECHIDA Essaghir

Etude expérimentale et théorique du Gisement Solaire pour la région de m’sila

The impact of doping electrical insulating fluids with nanoparticles on the thermal characteristics of the resulting nanofluids and heat transfer for cooling high-power transformers is covered in this study. The base fluid in this case was the synthetic ester. It investigated how adding Barium titanate (BaTiO3 )nanoparticles to dielectric fluids affected thermal characteristics, including convection and thermal conductivity. Comparisons were made between the cooling performance of basic fluids and nanofluids. An examination of the Rayleigh and Nusselt values confirms this comparison. The effects were represented as functions of the solid volume particle from the nanoparticles (0 ≤ φ < 10 %) and the thermal Rayleigh number (Rat = 103 and 106 ). The findings demonstrate that increasing the solid particle size of nanoparticles by 10 % increases the employed liquid's effectiveness as a conductor and raises the heat transfer rate by about 10 % compared to the base liquid.

Citation

Djedid TALOUB , Abdelkrim BOURAS , AMINA Amroune , Kheireddine Lattoui, Zied Driss, , (2024-08-12), “Enhancing heat transfer in high-pressure transformers: A study on nanoparticle-doped insulating fluids, Case Studies in Thermal Engineering, Vol:60, Issue:1, pages:104707, ELSEVIER

This paper was written to demonstrate the value of using nanofluids for cooling high power transformers while also providing current techniques for business and academia. A numerical analysis of the improvement caused by the cooling of a high voltage transformer using nanofluids has been done. A tank with a temperature source inside and a charge of mineral oil-barium titanate nanoparticles is used to study natural-convection. This study investigates the effects of variables on the thermal efficiency of the tank, including the thermal Rayleigh number and volume fraction. The results show that quenching varies with low and high Rayleigh thermal numbers and depends on the volume percentage of used nanoparticles. The effects were illustrated in thermal transfer rate representations as functions of the thermal Rayleigh number (Rat = 103 and 106 ) and the solid volume particle from the nanoparticles (0% ≤ φ < 10%). The findings showed that improving the solid volume particle of the nanoparticles by 10% causes the fluid being utilized to become more effectively conductive, which improves the rate of heat transfer by roughly 10% when compared to the case of the base fluid

Citation

Djedid TALOUB , Abdelkrim BOURAS , Ali J. CHAMKHA, Zied Driss, , (2024-04-13), EVALUATION OF THERMAL CONDUCTIVITY USING NANOFLUIDS TO IMPROVE THE COOLING OF HIGH VOLTAGE TRANSFORMERS, THERMAL SCIENCE:, Vol:28, Issue:4, pages:3081-3092, doiSerbia

The numerical investigation of heat transfer through natural convection in a vertically oriented annular cylinder using a nanofluid composed of Cu-water. The elliptical surfaces within the enclosure, characterized by the hot interior and cold exterior, were consistently upheld at unvarying temperatures denoted as Th and Tc, respectively. The resolution of the governing equations was accomplished through the utilization of the stream function-vorticity approach. To discretize the governing equations, the finite volume approach was employed. The specified ranges for the volume fraction of nanoparticles and the Rayleigh number were the following: 0<ϕ<0.08and〖10〗^3

Citation

AMINA Amroune , Abdelkrim BOURAS , Djedid TALOUB , ,(2023-12-02), Thermal Transfer with natural convection in a tilted annular cylinder filled with nanofluid,The 1st National Conference on physics and it's Applications (NCPA2023),ENS Bousaada

A numerical study of the natural convection of stationary laminar heat transfers in a horizontal ring between a heated square inner cylinder and a cold elliptical outer cylinder. This annular space is traversed by a Cu - water nanofluid. For different Rayleigh number and different volume fraction of nanoparticles. The system of equations governing the problem was solved numerically by the Fluent calculation code based on the finite volume method. Based on the Boussinesq approximation. The interior and exterior surfaces are kept at constant temperature. The study is carried out for Rayleigh numbers ranging from to . We have studied the effects of different Rayleigh numbers and volume fraction of nanoparticles on natural convection. The results are presented as isotherms, isocurrents, and local and mean Nusselt numbers. The aim of this study is to see the influence of the thermal Rayleigh number, and volume fraction of nanoparticles on the heat transfer rate.

Citation

AMINA Amroune , Abdelkrim BOURAS , Djedid TALOUB , ,(2023-11-29), Numerical study of natural convection in a horizontal ring between a cold elliptical outer cylinder and a heated square inner cylinder filled with nanofluid,1 st international Conference on Innovation Research in Materials and Nanothechnology (ICIRMN 2023),University of Ghardaia

In this paper, thermal transfer with natural convection in a tilted annular cylinder with a Cu-water nanofluid has been numerically studied. The hot interior and cold exterior elliptical surfaces of the enclosure were maintained at constant temperatures Th and Tc , respectively. The governing equations were solved by the stream functionvorticity approach. The finite volume approach was utilized to discretise the controlling equations. The volume fraction range of the nanoparticles and the Rayleigh number was as follows: 0 0 08 <φ< . and 4 6 10 Ra 10 < < , respectively. The inclination angles were 30 45 60 , and °° ° γ = . Results were given as isotherm contours, streamlines, average and local Nusselt numbers. The results indicate that the thermal transfer ratio increases with an increase in the tilt angle, regardless of the nanoparticle size values. and the impact of the inclination angle on the heating transfer rate is more important the higher the Rayleigh number and the more convection there is.

Citation

AMINA Amroune , Abdelkrim BOURAS , Djedid TALOUB , zied Deiss, , (2023-09-29), NUMERICAL STUDY OF HEATING TRANSFER BY NATURAL CONVECTION IN AN INCLINED ELLIPTICAL CYLINDER CHARGED WITH NANOFLUID, Int. J. of Applied Mechanics and Engineering, Vol:28, Issue:3, pages:28-41, UZ

The combination photovoltaic-thermal solar collector produces at the same time electricity gratitude to photovoltaic solar energy and warmth gratitude to thermal energy because it is known that the traditional photovoltaic panel produces three times more heat than the electricity. The increase in warmth inside the module is one of the principal reasons of the reduced performance of photovoltaic solar panels. Thus the necessity for a thermal evacuation technique. The benefit of a hybrid technique is the cooling of the photovoltaic cells gratitude to the circulation of a fluid, which will be warmed during its passage via the sensor. The novelty of this study is to recover this thermal energy by heating or drying. Previous dryers worked with thermal sensors thanks to the greenhouse effect, which gives only heat. The purpose of this paper is the realization experimental of a PV/T sensor and so the examination of the impact of different parameters on the energy performance of the PV/T sensor. The impacts recommend that this kind of collector is a nicely alternative to photovoltaic modules and thermal collectors seated individually.

Citation

Djedid TALOUB , Abdelkrim BOURAS , ALI Djegham , ,(2023-05-03), An experimental study of the thermal and electrical performance of hybrid sensor,International Conference on Solar Energy and Hybrid Systems (ICSEHS422),Laghouat, Algeria

The natural laminar and stable heat and mass convection in an enclosure defined by two horizontal confocal elliptical cylinders with normal and opposite buoyancy forces under uniform concentration and temperature has been numerically explored in this study. The physical Cartesian domain is transformed into an elliptical domain. For the numerical simulation, the equations of conservation of mass, momentum and energy as well as the boundary conditions are discretized by the numerical approach of finite volumes. The algebraic equations obtained were solved by the iterative Gauss-Seidel method. As a function of the effective variables, which are the Rayleigh number, the buoyancy force number N, the Prandtl number, and the Lewis number, the findings are shown as fields of velocities, temperatures, and concentrations as well as the average Nusselt and Sherwood numbers. The results showed that there is a critical buoyancy ratio Ncr = −1, where the mean Sherwood and Nusselt number values are minimal. Their values are decreased by rising values of N when N < Ncr and raised by rising values of N when N > Ncr, and raising the buoyancy ratio N's absolute value results in higher heat and mass transfer characteristics (averages Nusselt and Sherwood numbers)

Citation

Abdelkrim BOURAS , , (2023-05-01), Numerical simulation of the natural double-diffusive convection in an elliptical cylinder -Impact of the buoyancy force-, International Communications in Heat and Mass Transfer, Vol:144, Issue:, pages:106790, elsevier

The objective of this paper is to show the procedure to follow to analyze a physical phenomenon, with a simple and effective method. Mathematical stability examination was performed to define which resolution is stable and physically feasible. We have seen the approach and the steps that must be taken to go from a mathematical model to a numerical model. To do this, we used the Poisson equation as an example, and to show the results, we used the heat transfer equation. In real life, the most difficult step is not the numerical processing and analysis, but to understand the physical phenomenon and to translate it into a mathematical formulation. The finite difference approach is employed to resolving those equations numerically. The resulting schemes were resolved by the iterative GAUSS Seidel technique. These differential schemes have an approximate order 0 (h 2), and are absolute stable. Differential schemes are a linear algebraic equation system which solution can be solved by the Gaussian technique of elimination. This paper provides a good basis for the analysis of physical phenomena that deal with partial differential equations in 2D. In several sectors and branches, whether in the industrial framework

Citation

Abdelkrim BOURAS , , (2023-01-06), Modeling and numerical solution of the Laplace equation in 2D by the finite difference method case of the heat equation-Study of stability, Zeitschrift für angewandte Mathematik und Physik, Vol:2023, Issue:2023, pages:--, Research Square

The second part study of this paper presents a study of the double-diffusive natural convection phenomenon inside a space annulus, situated between two horizontal confocal elliptic cylinders filled with a laminar flow. The elliptical coordinates were utilized to transform the physical domain into one rectangular. The basic equations are discretized using the finite-volume method. Using a developed code, the study covers a wide range defined by (103 ≤ Rat ≤105), Le = 2, N = 1, and e = 0.52, 0.62, 0.72, 0.82. The studies cover the influence of the internal eccentricity parameter e1 on heat and mass transfer. The results present the isotherms, streamlines, and heat transfer. The local and average numbers for Sherwood and Nesselt are also displayed. The comparison with the published results showed that there is a good agreement.

Citation

Abdelkrim BOURAS , Djedid TALOUB , Mahfoud, Zied Driss, , (2023), Numerical Research of Double‐Diffusive Natural Convection in Elliptical Cylinders: Influence of Internal Eccentricity, International Journal of Engineering Research in Africa, Vol:63, Issue:, pages:33-44, Trans Tech Publications Ltd

The development of modern technology in microelectronics and power engineering requires the creation of efficient cooling systems. This is made possible by the use of special fin technology inside the cavity or special heat transfer Ethylene glycol-copper nanofluids to intensify the heat removal from the heat-generating elements. A numerical study of the natural convection of stationary laminar heat transfers in a closed rectangular cavity with a local source of internal volumetric heat generation. For different Rayleigh numbers and different volume fractions of nanoparticles. The system of equations governing the problem was solved numerically by the fluent computer code based on the method of finite volumes. Based on the Boussinesq approximation. Interior and exterior surfaces are maintained at a constant temperature. The study is carried out for Rayleigh numbers ranging from 104 to 106. The effects of different Rayleigh numbers and volume fractions of nanoparticles on natural convection have been studied. The results are presented as isotherms, isocurrents, and local and mean Nusselt numbers. The aim of this study is to see the influence of the thermal Rayleigh number and the volume fraction of the nanoparticles on the rate of heat transfer.

Citation

Abdelkrim BOURAS , Djedid TALOUB , AMINA Amroune , Zied Driss, , (2022-08-31), The Impact of Nanofluid on Natural Convection in an Isosceles Rectangular Container with a Heat Source, Advanced Engineering Forum, Vol:47, Issue:, pages:19-28, Trans Tech Publications Ltd

In this paper a numerical study of natural convection of stationary laminar heat transfers in a horizontal ring between a heated square inner cylinder and a cold elliptical outer cylinder is presented. A Cu-water nanofluid flows through this annular space. Different values of the Rayleigh number and volume fraction of nanoparticles are studied. The system of equations governing the problem was solved numerically by the fluent calculation code based on the finite volume method and on the Boussinesq approximation. The interior and exterior surfaces are kept at constant temperature. The study is carried out for Rayleigh numbers ranging from 3 10 to 5 10 . We have studied the effects of different Rayleigh numbers and volume fraction of nanoparticles on natural convection. The results are presented as isotherms, isocurrents, and local and mean Nusselt numbers. The aim of this study is to study the influence of the thermal Rayleigh number and volume fraction of nanoparticles on the heat transfer rate.

Citation

Abdelkrim BOURAS , Djedid TALOUB , Bureau de la stratégie de numérisation , Zied Driss, , (2022), Heat Transfer By Natural Convection from a Heated Square Inner Cylinder to Its Elliptical Outer Enclosure Utilizing Nanofluids, International Journal of Applied Mechanics and Engineering, Vol:27, Issue:2, pages:22-34, sciendo

The combination photovoltaic-thermal solar collector produces at the same time electricity gratitude to photovoltaic solar energy and warmth gratitude to thermal energy because it is known that the traditional photovoltaic panel produces three times more heat than the electricity. The increase in warmth inside the module is one of the principal reasons of the reduced performance of photovoltaic solar panels. Thus the necessity for a thermal evacuation technique. The benefit of a hybrid technique is the cooling of the photovoltaic cells gratitude to the circulation of a fluid, which will be warmed during its passage via the sensor. The novelty of this study is to recover this thermal energy by heating or drying. Previous dryers worked with thermal sensors thanks to the greenhouse effect, which gives only heat. The purpose of this paper is the realization experimental of a PV/T sensor and so the examination of the impact of different parameters on the energy performance of the PV/T sensor. The impacts recommend that this kind of collector is a nicely alternative to photovoltaic modules and thermal collectors seated individually.

Citation

ALI Djegham , Djedid TALOUB , Abdelkrim BOURAS , ZIED DRISS, , (2022), An empirical investigation of the electrical and thermal performance of photovoltaic-thermal hybrid sensor (PV/T), WSEAS TRANSACTIONS on CIRCUITS and SYSTEMS, Vol:21, Issue:, pages:65-73, WSEAS

The numerical study on the improvement of the cooling of a microprocessor by the use of Nanofluids has been made. Natural convection is analyzed in a box fence with a temperature source encountered at its lower border and loaded with an Ethylene Glycol-Copper nanoparticle. This article explores the influences of relevant aspects such as thermal Rayleigh number, solid volume fraction, and enclosure dimensions on the thermal efficacy of the box fence, which are enhanced with an enlargement in thermal Rayleigh number and solid volume fraction. The results also illustrate that the change of the warmth transfer rate concerning the box dimensions of the enclosure is unlike at inferior and elevated thermal Rayleigh numbers. A simile is offered between the upshots got and the literature. Results were presented in terms of heat transfer rate depending on thermal Rayleigh number (Rat = 103 , and 106 ), nanoparticle solid volume fraction (0 ≤ φ < 5%), and box dimensions. The results show that raising the solid volume fraction of the nanoparticles (φ = 5%) drive a rise in the efficient conductivity of the working fluid and consequently the improvement of the heat transfer rate by approximately ≈ 10% per compared to the base fluid case.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Deiss, , (2022), Numerical study on the improvement of the cooling of ah microprocessor by the use of nanofluids, WSEAS Transactions on Heat and Mass Transfer, Vol:17, Issue:1, pages:66-79, WSEAS

In this document, a numerical study of the natural convection of steady-state laminar heat transfer in a horizontal ring between a heated hexagonal inner cylinder and a cold hexagonal outer cylinder. A Cu - water nanofluid traverses this annular space. The system of equations governing the problem was solved numerically by the fluent calculation code based on the finite volume method. Based on the Boussinesq approximation. The interior and exterior sides from the two cylinders are maintained at a fixed temperature. We investigated the impacts of various thermal Rayleigh numbers (103≤ Rat ≤2.5x105), and the volume fraction from the nanoparticles (0≤ Ø ≤0.12) on fluid flow and heat transfer performance. It is found that in high thermal Rayleigh numbers, a thin thermal boundary layer is illustrated at the flow that heavily strikes the ceiling and lower from the outer cylinder. In addition, the local and mean Nusselt number from a nanofluid are enhanced by enhancing the volume fraction of the nanoparticles.The results are shown within the figure of isocurrents, isotherms, and mean and local Nusselt numbers. Detailed results of the numerical has been compared with literature ones, and it gives a reliable agreement.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Driss, , (2022), Numerical Study of Heat Transfer by Natural Convection in Concentric Hexagonal Cylinders Charged with a Nanofluid, WSEAS Transactions on Heat and Mass Transfer, Vol:17, Issue:, pages:19-28, WSEAS

This article has been to make available modern methodologies for both industry and academia, also highlighting the importance of using nanofluids for cooling high power transformers. The numerical study on the improvement of the cooling of a high voltage transformer by the use of nanofluids has carried out. Natural convection analyzed in a tank with a temperature source encountered inside and charged with a mineral oil-barium titanate nanoparticle. This article explores the influences of aspects such as the thermal Rayleigh number, and the solid volume fraction on the thermal efficiency of the tank. The results show that the cooling change related to the nanoparticle volume fraction used and differs from the low and high Rayleigh thermal numbers. The results were presented in terms of heat transfer rate as a function of the thermal Rayleigh number (Rat = 103 and 106), and of the solid volume fraction of the nanoparticles (0 ≤ φ < 10%). The results show that increasing the solid volume fraction of the nanoparticles (φ = 10%) leads to an increase in the effective conductivity of the working fluid and consequently the improvement of the heat transfer rate by approximately ≈ 10% per compared to the case of the base fluid.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Driss, ,(2022), Numerical study on the improvement of the cooling of a high voltage transformer by the use of nanofluids,Conference on Engineering Science, JSI’2022-001 October 14-16, 2022, Sfax, Tunisia,Tunisia

In this paper, we are interested in the design and manufacture of an aerovoltaic system for drying food products and medical plants. In these experiments, we used an indirect solar dryer, where in the latter we believe the heat from the drying chamber by a hybrid photovoltaic (thermoelectric) panel reaches the temperature it comes out of the hybrid collector of 60.8 - 69.9 degrees Celsius combined with a greenhouse effect. The main objective of these experiments is to use free energy (the sun) to study drying kinetics and water content. The results obtained in this study were as follows: to dry 150 grams of Mint, the desired temperature range is 41.1 - 49.9 °C for 3 hours and for 710 grams of Tomato 58.4 - 68.8 °C under 4 hour circumstances. . The purpose of the drying process of these products is that the wide use of these products dried, while preserving the nutritional value of the product and good quality.

Citation

Abdelkrim BOURAS , Djedid TALOUB , ALI Djegham , Zied Driss, ,(2022), Design and construction of a solar dryer using an aerovoltaic system for drying food products,Conference on Engineering Science, JSI’2022-001 October 14-16, 2022, Sfax, Tunisia,Tunisia

The purpose of this paper is to numerically study the double-diffusive natural convection in a space annulus, situated between two horizontal confocal elliptic cylinders filled with a Newtonian fluid, is presented. The elliptical coordinates are used to transform the physical domain into a rectangular one. The basic equations are discretized using the finite-volume method. Using a developed code, The study covers a wide range for (103 ≤ Ra ≤105 ), Le=2 , N=1 , e = 0.52, 0.62, 0.72, 0.82. Effects of the internal parameter eccentricity e1 on heat and mass transfer are studied in detail. Results are presented in the form of stream lines, isotherm plots, and local and average Nusselt numbers.A comparison was made with the published results and a good agreement was found.

Citation

AMINA Amroune , Abdelkrim BOURAS , Djedid TALOUB , ,(2021-11-15), Numerical investigation of double diffusive natural convection in elliptical cylinders: part -II- Influence of internal eccentricity,International conference on Mechanical Sciences ICMS'21,University of Oum El Bouaghi

During this first paper, numerical research from the natural convection of steady-state laminar heat transfer into a horizontal ring within a heated internal elliptical surface and a cold external square surface is presented. A Cu - water nanofluid, traverses this annular space. For different thermal Rayleigh numbers varying from 103 to 2.5x105 and different volume fractions from the nanoparticles. The arrangement from equations directing the problem was resolved numerically with the Fluent computational language founded on the finite volume approach. Based approaching the Boussinesq approach. The interior and exterior surfaces from the two cylinders are maintained at a fixed temperature. We investigated the impacts of various thermal Rayleigh numbers, the volume fraction from the nanoparticles, and the effect of the eccentricity of the internal cylinder on the natural convection. The results are shown within the figure of isocurrents, isotherms, and mean and local Nusselt numbers. The objective of this investigation is to examine the impact of different parameters on the heat transfer flow.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Driss, , (2021), Numerical Investigation of Heat Transfer with Natural Convection in a Regularly Heated Elliptical Cylinder Submerged in a Square Fence Loaded With a Nanofluid, International Journal of Mathematical Models and Methods in Applied Sciences, Vol:15, Issue:1, pages:223-232, WSEAS

The combination photovoltaic-thermal solar collector produces at the same time electricity gratitude to photovoltaic solar energy and warmth gratitude to thermal energy because it is known that the traditional photovoltaic panel produces three times more heat than the electricity. The increase in warmth inside the module is one of the principal reasons of the reduced performance of photovoltaic solar panels. Thus the necessity for a thermal evacuation technique. The benefit of a hybrid technique is the cooling of the photovoltaic cells gratitude to the circulation of a fluid, which will be warmed during its passage via the sensor. The novelty of this study is to recover this thermal energy by heating or drying. Previous dryers worked with thermal sensors thanks to the greenhouse effect, which gives only heat. The purpose of this paper is the realization experimental of a PV/T sensor and so the examination of the impact of different parameters on the energy performance of the PV/T sensor. The impacts recommend that this kind of collector is a nicely alternative to photovoltaic modules and thermal collectors seated individually.

Citation

ALI Djegham , Djedid TALOUB , Abdelkrim BOURAS , ,(2021), Experimental study of a dehydrator by a hybrid aerovoltaic system (photovoltaic- thermal),,International conference on Mechanical SciencesICMS'21 University Oum El Bouaghi 15th 16 November 2021,University Oum El Bouaghi

This article is the second of a three-part document, which is to develop and validate the finite difference method applied to the thermal conduction, has a spatial variable and state with a heat source in a wall of a square shaped oven following a single direction, which results a differential equation partial of parabolic. The finite difference method is used to solve these equations numerically. The obtained schemes have been solved by the iterative method of GAUSS Seidel. This difference schemes have approximation order 0(τ+h2), and absolutely stable. The difference schemes are a system of linear algebraic equations whose solution can be found by the method of Gaussian elimination. View of the tri diagonal structure of this system can save the amount of calculation using the algorithm next sweep. The numerical results obtained prove the stability and the convergence of the schemes with differences and the computation algorithm elaborated

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Driss, , (2020), Numerical Resolution of the Heat Equation in the Square Form Four-Part- II-, Mathematical Modelling of Engineering Problems, Vol:7, Issue:2, pages:205-211, International Information and Engineering Technology Association (IIETA)

This paper is the first part of a two‐part study, and it presented numerical research of double‐diffusive natural convection within an annulus area, situated in two horizontal confocal elliptic solids charged by a Newtonian fluid. The elliptical coordinates were used to transform the physical domain into a rectangular one. To resolve the governing equations and the boundary layer conditions, a calculator code based on the finite volume approach was developed. The details of the influences of thermal Rayleigh number on heat and mass transfer were investigated. Results obtained were compared with those existing in other reasearch works.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Mahfoud Djezzar, Zied Driss, , (2020), Numerical research of double‐diffusive natural convection in elliptical cylinders: Effect of thermal Rayleigh number, Heat Transfer, Vol:49, Issue:, pages:2194-2205, John Wiley and Sons

A numerical study of the natural convection of laminar heat transfers in the stationary state in a half-elliptic inclined cavity, which represents a continuation of the work done, we studied the influence of the tilt of the cavity by varying the angle — entered 0 degrees, which corresponds to the horizontal cavity, up to 15 degrees. For each value of δ we varied the Rayleigh number from 2.13 103 to 106. The system of equations governing the problem solved numerically by the fluent calculation code based on the finite volume method. Based on the Boussinesq approximation. Both bottom and upper walls maintained at a constant temperature. The interest of this study is to see the influence of the tilt of the half-elliptic cavity on the structure of the flow and the distribution of temperature. These results can exploited in semi-elliptic agricultural greenhouses that rest on sloping soils. We chose a Prandtl number 0.71 that corresponds to the air. Keywords: Heat transfer; half-elliptical; Natural convection; Laminar flow; Multicellular; CFD simulation

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Driss, , (2020), Effect of the Soil Inclination on Natural Convection in Half-Elliptical Greenhouses, International Journal of Engineering Research in Africa, Vol:50, Issue:, pages:70-78, Trans Tech Publications Ltd

This paper deals with numerical investigation of a natural convective flow in a horizontal annular space between a heated square inner cylinder and a cold elliptical outer cylinder with a Newtonian fluid. Uniform temperatures are imposed along walls of the enclosure. The governing equations of the problem were solved numerically by the commercial code Fluent, based on the finite volume method and the Boussinesq approximation. The effects of Geometry Ratio GR and Rayleigh numbers on fluid flow and heat transfer performance are investigated. The Rayleigh number is varied from 103 to 106 . Throughout the study the relevant results are presented in terms of isotherms, and streamlines. From the results, we found that the increase in the Geometry Ratio B leads to an increase of the heat transfer coefficient. The heat transfer rate in the annulus is translated in terms of the average Nusselt numbers along the enclosure's sides. Tecplot 7 program was used to plot the curves which cleared these relations and isotherms and streamlines which illustrate the behavior of air through the channel and its variation with other parameters. The results for the streamlines, isotherms, local and average Nusselt numbers average Nusselt numbers are compared with previous works and show good agreement.

Citation

Abdelkrim BOURAS , Djedid TALOUB , Zied Driss, , (2020), EFFECT OF RAYLEIGH NUMBER ON INTERNAL ECCENTRICITY IN A HEATED HORIZONTAL ELLIPTICAL CYLINDER TO ITS COAXIAL SQUARE ENCLOSURE, Int. J. of Applied Mechanics and Engineering, Vol:25, Issue:3, pages:17-29, sciendo

— In this paper, we study the heat transfer in turbulent natural convection in a t wo- dimensional cavity with a t rapezoidal section and isoscales filled out of air with as height H =2.5 m. In these conditions, the side walls are differentially heated while the horizontal walls are adiabatic. The k-ε turbulence model with a small Reynolds number was integrated in our calculation code. The governing equations of the problem were solved numerically by the commercial CFD code Fluent; which is based on t he finite volume method and the Boussinesq approximation. The elaborated model is validated from the experimental results in the case of the turbulent flow in a square cavity. Then, the study was related primarily to the influence of the slope of the side walls of the cavity on the dynamic behavior and the heat transfer within the cavity.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Driss, , (2020), Numerical Study of the Turbulent Natural Convection in a Trapezoidal Cavity: Influence of the Inclination of the Lateral Walls, INTERNATIONAL JOURNAL OF MATHEMATICAL MODELS AND METHODS IN APPLIED SCIENCES, Vol:14, Issue:1, pages:41-47, North Atlantic University Union

Dans cet article, Une analyse numérique de la convection naturelle laminaire dans une quarte ellipse remplie d'air ayant des ailettes chaudes et froides sur les murs adjacents a été effectuée pour examiner le flux de chaleur et de fluide. Les solutions numériques sont obtenues en utilisant un code commercial de dynamique des fluides numérique, FLUENT, en utilisant la méthode des volumes finis. Les effets du nombre de Rayleigh, de l'emplacement des ailettes et de la longueur des ailettes sur le nombre de Nusselt moyen, Numoy, ainsi que la fonction du flux et les champs de température sont étudiés pour la plage de Rat de 104 à 5x106.

Citation

Djedid TALOUB , Abdelkrim BOURAS , ,(2020), Analyse numérique de la convection naturelle laminaire dans une quarte ellipse avec une ailette adiabatique fixée au mur vertical chaud,1ère Conférence Nationale sue la Transition Energétique en Algérie,University M'sila

The purpose of this work is to show the effect of external parameters: albedo and wind speed) on a solar collector inclined plane. The method used consists in cutting the collector into fictitious slices (05 meshes) of length Δx in the direction of the flow of the heat transfer fluid and writing the balance sheets of the exchanges which intervene at the levels of the 06 nodes: from the outside of the glass, the inside of the glass, the absorber, in the peddler fluid as well as the inside and the outside of the insulation. It is convenient for this to use the analogies that exist between the transfer of heat and electricity, the results obtained are the temperatures at the nodes

Citation

Abdelkrim BOURAS , , (2019-01-11), Study of The Influence of External Parameters on ThermalPerformance of a Solar Water Collector, Journal of Advanced Research in FluidMechanics and Thermal Sciences, Vol:53, Issue:2, pages:213-222, Academia Baru

The purpose of this work is to show the effect of external parameters: albedo and wind speed) on a solar collector inclined plane. The method used consists in cutting the collector into fictitious slices (05 meshes) of length Δx in the direction of the flow of the heat transfer fluid and writing the balance sheets of the exchanges which intervene at the levels of the 06 nodes: from the outside of the glass, the inside of the glass, the absorber, in the peddler fluid as well as the inside and the outside of the insulation. It is convenient for this to use the analogies that exist between the transfer of heat and electricity, the results obtained are the temperatures at the nodes.

Citation

Abdelkrim BOURAS , Djedid TALOUB , Abdelhadi Beghidja, Zied Driss, , (2019), Laminar Natural Convection Study in a Horizontal HalfElliptical Enclosure Using Heater on Horizontal Wall, Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, Vol:53, Issue:2, pages:223-233, : www.akademiabaru.com/arfmts.html

A numerical study of the natural convection of the laminar heat transfers in the stationary state was developed in a horizontal ring and compared between a heated trapezoidal internal cylinder and a cold elliptical outer cylinder. This annular space is traversed by a Newtonian and incompressible fluid. The Prandtl number is set to 0.7 (air case) for different Rayleigh numbers. The system of equations controlling the problem was solved numerically by the calculation of code fluent based on the finite volume method. In these simulations the Boussinesq approximation was considered. The inner and outer surfaces are kept at a constant temperature. The study is performed for Rayleigh numbers ranging from 103 to 105. Indeed, the effects of different numbers of thermal Rayleigh on natural convection were studied. The results are presented in the form of isotherms, isocurrents, local and average numbers of Nusselt. The purpose of this work is to study the influence of the thermal Rayleigh number, and the change of the angle of inclination of the trapezoidal lateral walls on the structure of the flow and the distribution of the temperature.

Citation

Abdelkrim BOURAS , Djedid TALOUB , , (2019), Numerical investigation of natural convection phenomena in uniformly heated trapezoidal Cylinder inside an elliptical Enclosure, Journal of Computational Applied Mechanics (JCAMECH), Vol:50, Issue:2, pages:315-323, https://jcamech.ut.ac.ir/

A numerical study of the natural convection of laminar heat transfer in the stationary state in a horizontal annular space between a heated square inner cylinder and a cold elliptical outer cylinder was investigated. This annular space is traversed by a Newtonian and incompressible fluid. The Prandtl number is set to 0.71 (air case) for different Rayleigh numbers. The governing equations of the problem were solved numerically by the commercial code Fluent, based on the finite volume method and the Boussinesq approximation. The inner and outer surfaces are isothermal. The study was performed for Rayleigh numbers ranging from 1.3 × 103 to 5.5× 105 . Particularly, we have studied the effects of different thermal Rayleigh numbers on natural phenomenon convection. The results were presented in the form of isotherms, streamlines, and local and average Nusselt numbers. The purpose of this study is to observe the influence of the thermal Rayleigh number on the structure of the flow and distribution of the temperature.

Citation

Abdelkrim BOURAS , Djedid TALOUB , Mahfoud Djezzar, Zied Driss, , (2018), Natural convective heat transfer from a heated horizontal elliptical cylinder to its coaxial square enclosure, Mathematical Modelling of Engineering Problems, Vol:5, Issue:4, pages:379-385, Journal homepage:http://iieta.org/Journals/MMEP

The work presented in this paper is the numerical study of a thermal converter. The main objective of the work is to study the effect of certain parameters on a flat solar collector. We are particularly interested in determining the influence of water flow on the operating characteristics of the solar collector and the effect of the orientation of a surface on the energy received. We have realized a mathematical model simulating the thermal behavior of collectors, to solve the mathematical model using an iterative method of Gauss-Seidel. According to the results obtained on this device, we note that: The inclination between 30 and 37 ° gives the best performances. The outlet temperature is higher for low flow. The overall efficiency increases with the flow of water.

Citation

Abdelkrim BOURAS , Djedid TALOUB , N. Bellel, Badis Bakri, Driss Zied, , (2018), Influence of the Debit and the Orientation of a Solar Converter, International Journal of Mechanics and Energy (IJME), Vol:6, Issue:1, pages:36-41, http://www.ijme.aicme.net/

L'amélioration des performances des capteurs solaires plans consiste à limiter les pertes thermiques entre l’absorbeur et l'environnement. Notre étude consiste à mettre en présence l’influence du flux solaire et la matière isolante Sur la tempéra ture de sortie du fluide caloporteur et le rendement d’un capteur solaire plan incliné. On découper le capteur en tranches fictives dans le sens de l’écoulement du fluide caloporteur et à établir les bilans des échanges qui interviennent aux niveaux des nœuds considérés : l’extérieure de la vitre, l’intérieur de la vitre, l’absorbeur, dans le fluide colporteur ainsi que l’intérieure et l’extérieur de l’isolant. Il est commode pour cela d’utiliser l’analogie qui existe entre les transferts de chaleur et les lois électrique, les profils des températures au niveau des nœuds principaux résultats commentés.

Citation

Abdelkrim BOURAS , Djedid TALOUB , Driss Zied, ,(2018), Study of the Thermal Performance of a Solar Water collector,Fourth International Conference on Mechanic and Energy (ICME'2018),Hammamet, Tunisia

In the field of photo-thermal conversion, many applications have been highlighted, the work presented here is part of the contribution of the design and simulation of solar thermal converters, A digital investigation was carried out to put the effect of the parameters external: Alberdo and wind speed on the thermal performance of water-cooled solar collectors, For this we developed a calculation program to present the numerical results We found that global solar radiation save optimum values in desert areas and the wind speed has a relatively large influence on the efficiency of the solar thermal converters.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Zied Driss, ,(2018), Performance of the Flat Solar Energy Collectors in Space Heating,The fourth International Conference on Mechanics and Energy ICME'2018,Hammamet, Tunisia

The work presented in this paper is the numerical study of a thermal converter. The main objective of the work is to study the effect of certain parameters on a flat solar collector. We are particularly interested in determining the influence of water flow on the operating characteristics of the solar collector and the effect of the orientation of a surface on the energy received. W e have realized a mathematical model simulating the thermal behavior of collectors, to solve the mathematical model using an iterative method of Gauss-Seidel. According to the results obtained on this device, we note that: The inclination between 30 and 37 ° gives the best performances. The outlet temperature is higher for low flow. The overall efficiency increases with the flow of water.

Citation

Abdelkrim BOURAS , Djedid TALOUB , N. Bellel, B. Bakri, ,(2017), Influence of the Debit and the Orientation of a solar Converter,Internhanic and Energy ICME'2017ational Conference on Mec,Sousse, Tunisia

Dans cette communication nous avons effectué une simulation numérique de convection naturelle dans une enceinte fermée de grande taille (de 2.46m de hauteur) et comportant des parois verticales maintenues à des températures imposées constantes, tandis que les autres parois sont adiabatiques, Le modèle de turbulence LES à faible nombre de Reynolds a été intégré dans notre code de calcul. Le système d’équations gouvernant le problème est résolu numériquement à l'aide d'une méthode aux volumes finis en se basant sur l'algorithme SIMP LE. Le modèle élaboré est d'abord validé à partir des résultats expérimentaux et numériques dans le cas d'un écoulement turbulent dans une cavité carrée. Nous étudions le champ dynamique, pour des valeurs du nombre de Rayleigh 1.4x1011. Deux principales zones ont été vérifiées : le cœur de la cavité et les couches limites en développement le long des parois actives et la partie haut de la cavité. Nous présentons la stratification thermique effectuées dans la cavité. Ensuite, les profils de température à dif férentes altitudes sont commentés et les transferts de chaleur sont quantifiés. Toutes ces études ont été menées pour de très grands nombre de Rayleigh.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Beghidja Abdelhadi, ,(2017), Etude numérique de champs dynamique des écoulements de convection naturelle à nombre de Rayleigh élevé dans la partie haute de la cavité,3éme Conference Internationale de Mécanique,Annaba, Algérie

This is the second of a three-part document, which is to develop and validate the finite difference method applied to the thermal conduction in an unsteady state with a heat source in a square shaped oven, the resulting system of equations is a pa rtial differential equation of parabolic type. This difference scheme has approximation order ( ) and absolutely stable. The difference scheme is a system of linear algebraic equations whose solution can be found by the method of Gaussian elimination. View of the tri diagonal structure of this system can save the amount of calculation using the algorithm next sweep.

Citation

Djedid TALOUB , Abdelkrim BOURAS , Abdelhadi Beghidja, ,(2017), Resolution of the heat equation in the square form Oven Part-II-,International Conference on Mechanics and Energy ICME'2017,Sousse, Tunisia

Dans cette communication nous avons effectué une simulation numérique de convection naturelle dans une enceinte fermée de grande taille (de 2.46m de hauteur) et comportant des parois verticales maintenues à des températures imposées constantes, tandis que les autres parois sont adiabatiques, Le modèle de turbulence LES à faible nombre de Reynolds a été intégré dans notre code de calcul. Le système d‘équations gouvernant le problème est résolu numériquement à l'aide d'une méthode aux volumes finis en se basant sur l'algorithme SIMPLE. Le modèle élaboré est d'abord validé à partir des résultats expérimentaux et numériques dans le cas d'un écoulement turbulent dans une cavité carrée. Nous étudions le champ thermique, pour des valeurs du nombre de Rayleigh 1.4x1011. .Deux principales zones ont été vérifiées : le coeur de la cavité et les couches limites en développement le long des parois actives et la partie haute de la cavité, on a remarqué que l‘état de couches limites thermiques est très turbulent et relativement épaisses quand le nombre de Rayleigh est élevé. Nous présentons la stratification thermique effectuées dans la cavité. Il ressort de notre simulation que la partie centrale de cette cavité est stratifiée en température. Ensuite, les profils de température à différentes hauteurs sont commentés et les transferts de chaleur sont quantifiés. Toutes ces études ont été menées pour nombre de Rayleigh élevés

Citation

Djedid TALOUB , Abdelkrim BOURAS , Beghidja, Abdelhadi, ,(2016), Etude numérique de champs thermique des écoulements de convection naturelle à hauts nombre de Rayleigh dans la partie haute d’une cavitédifférentiellement chauffée,Deuxièmes Journées Internationales de Physique de Constantine,Constantine