Papers by Draoui Belkacem
International Conference of Fluid Flow, Heat and Mass Transfer, 2016
Building insulation materials are the building materials which form the thermal envelope of a bui... more Building insulation materials are the building materials which form the thermal envelope of a building or otherwise reduce heat transfer. Many insulations are made from petrochemicals and may be a concern for those seeking to reduce the use of fossil fuels and oil.Some insulation materials have health risks, some so significant the materials are no longer allowed to be used but remain in use in some older buildings such as asbestos fibers and urea. Also, the cost can be high compared to traditional insulation. This work presents a study of numerical simulation aiming at the role and the influence of the insulation by the mud Reduced like a local material in the town of Bechar located in the Sahara of Algeria, or one is interested in a comparative study for pursued these goals. In this context, an analogy was used for the functions which are discretized by the finite difference method and integrated in the CFD code which is based on the finite volume method. The effects of various physical parameters such as, the Rayleight number, insulation by the mud as local materials in Sahara of Algeria are studied. The Rayleight nember varies between 10 3 and 10 6 , .The obtained results are of fundamental interest and can be relevant for the development of efficient heat exchangers. This technique has proven that the rate of heat transfer is minimized up to 37%.
Instrumentation Mesure Métrologie, 2021
During a forced convection sun drying and storage operation, the equilibrium water content of a p... more During a forced convection sun drying and storage operation, the equilibrium water content of a product to be dried is critical. These figures are frequently derived using isothermal sorption curves. The calculation of isotherms is a necessary step in determining the distribution and intensity of water connections in products. for that this paper concentrates on the experimental determination of the adsorption-desorption isotherms for various temperatures (40, 50, and 60℃) of the Nicotiana Tabacum L plants. From which we had established the relationship between the water activity and the water content in the product. However, the aforementioned determination was carried out by the static gravimetric method. Eight saturated salt solutions have been utilized in applications such as (KOH, KCl, MgCl2, MgNO3, K2CO3, BaCl2, K2SO4, and NaCl). Hygroscopic equilibrium was completed after 13 days for temperature 40℃, 11 days for 50℃, and 9 days for 60℃. The overall experimental sorption curve...
建物外皮を通しての熱移動に及ぼす種々の動作温度下でのポリスチレン断熱材の熱伝導率の変化の影響【Powered by NICT】
Applied Thermal Engineering, 2016
12éme Séminaire International sur la Physique Énergétique (SIPE 12) Béchar: 23, 24 et 25 février 2015
EPJ Web of Conferences, 2016
This study focuses on the numerical simulation of heat transfer by natural convection in a rectan... more This study focuses on the numerical simulation of heat transfer by natural convection in a rectangular enclosure, filled with a liquid metal (low Prandtl number) partially heated from below with a sinusoidal temperature. The value of the study lies in its involvement in the crystal growth for the manufacture of semiconductors and electronics cooling. Indeed, the occurrence of convection during crystal growth can lead to in homogeneities that lead to striations and defects that affect the quality of the crystals obtained by the Bridgman techniques or Chochrawlski. Temperature of the oscillations, due to the instabilities of the convective flow in the liquid metal, also induces non-uniform cooling in the solidification front. Convection is then studied in order to reduce it. A modelling of the problem in two dimensions was conducted using Comsol computer code that is based on the finite element method, by varying the configuration of the control parameters, namely, the Rayleigh number, the nature of fluid (Prandtl number) and amplitude of temperature on heat transfer rate (Nusselt number) on convective structures that appear. This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits distribution, and reproduction in any medium, provided the original work is properly cited.
International Symposium on Greenhouse Cooling, 2006
Although natural ventilation plays an important role in the affecting greenhouse climate, as defi... more Although natural ventilation plays an important role in the affecting greenhouse climate, as defined by temperature, humidity and CO 2 concentration, particularly in Mediterranean countries, little information and data are presently available on full-scale greenhouse ventilation mechanisms. In this paper, we present a new method for selecting the parameters based on evolutionary algorithms which optimize the choice of parameters by minimizing a cost function. The simulator was based on a published model with some minor modifications as we were interested in the parameter of ventilation. The function is defined by a reduced model that could be used to simulate and predict the greenhouse environment, as well as the tuning methods to compute their parameters. This study focuses on the dynamic behavior of the inside air temperature and humidity during ventilation. Our approach is validated by comparison with some experimental results. Various experimental techniques were used to make full-scale measurements of the air exchange rate in a 400 m 2 plastic greenhouse. In recent years, evolutionary algorithms been applied to a variety of dynamic optimization problems. The model which we propose, based on natural ventilation parameters optimized by evolutionary algorithms, was compared with the measurements and with other results published in the literature.
EPJ Web of Conferences, 2018
Among the ways of energy transfer by conduction is that of molecular interaction, in which the gr... more Among the ways of energy transfer by conduction is that of molecular interaction, in which the greater motion of a molecule at a higher energy level (temperature) imparts energy to adjacent molecules at lower energy levels. This type of transfer is present, to some degree, in all systems in which a temperature gradient exists and in which molecules of a solid, liquid, or gas are present. So, in heat transfer, the thermal conductivity of a substance is an intensive property that indicates its ability to conduct heat In particular in the building sector. The thermal flux is often measured with a mathematical analysis but for the same material, on the other hand the estimate will be disruptive and sometimes very difficult when the material changes. In this paper, a single equation for predicting heat flux of different materials is given.
Experimental Study and Thermal Modeling (Linearization of Nonlinear System) of Building: Southwest Algeria Case
Numeric Simulation of the Natural Convection in a Horticultural Greenhouse Heated from Below (By the Use of the CFD)
Elaboration d’un logicie l pour l’estimation de rayonnement solaire e n Algérie
Dans ce travail nous avons élaboré un logiciel en utilisant le langage de la programmation Delphi... more Dans ce travail nous avons élaboré un logiciel en utilisant le langage de la programmation Delphi7 pour l’estimation du rayonnement solaire en Algérie . Le logiciel contient une base de donné dans laquelle les 48 willayas sont introduits avec ses caractéristiques tel que latitude, longitude et l'altitude. Nous citons le modèle de ASHRAE, et celui du LUI & JORDON. Le programme nous donne la possibilité de comparés les valeurs estimées par les modèle théoriques et les valeurs mesurés par la station météorologie de laboratoire de recherche ENERGARID. Nous avons constaté une bonne concordance.
Energy Procedia, 2016
The aim of this article is to study by numerical simulation with the TRNSYS-COMIS software, the t... more The aim of this article is to study by numerical simulation with the TRNSYS-COMIS software, the thermo-aeraulic behavior of a traditional house with a horizontal opening in the central space of the house, and in the city of Kenadsa (southwestern Algeria, hot dry climate). In these regions with hot, dry climates, traditional architecture was developed using empirical knowledge provided by a combination of passive strategies for thermal control, results of a thorough knowledge of weather conditions. The paper presented in the context of this work is related to an attempt to bioclimatic architectural approach, to reduce the energy consumption of heating and cooling of buildings in these areas, while improving thermal comfort. This approach aims to improve the quality of the built environment by developing a new or updated conceptual model, firstly by enhancing local natural resources, and secondly by processing information through scientific tools . Several variants were examined: dimension of the horizontal opening, combination with other openings (of ventilation holes in the parts around the central space, and stairwell) and the effect of building materials used in the building fabric. The proposed model for the simulation of horizontal opening home is validated with an experimental study . The results of this study are presented in the form of hot and cold hours in a year, maximum and minimum indoor comfort temperatures, and frequency of effective ventilation per person as air quality performance indicator in each room.
IOSR Journal of Mechanical and Civil Engineering, 2016
During these last years the current concerns about global warming and depletion of fossil resourc... more During these last years the current concerns about global warming and depletion of fossil resources have renewed the interest of the development of renewable energy in the electricity generation sector. Among them, solar energy holds a privileged position thanks to its technological progress and its associated costs comparatively low. The use of the technique based on the solar tower chimney effect has proved to be a promising approach for future applications. The work presented in this article is a feasibility study of a solar power plant chimney effect for the production of electrical energy to ensure the electricity needs of the entire Saharan region of Beni Abbes. The goal is to see the influence of certain parameters on the electrical output of the plant.
Optimization of ANN Adaptation Time for the Modeling of Greenhouse Climate Using Wavelet Transform
International Review on Modelling and Simulations (IREMOS), 2016
In this paper we optimize the adaptation time taken by an Artificial Neural Network (ANN) to mode... more In this paper we optimize the adaptation time taken by an Artificial Neural Network (ANN) to model the indoor climate greenhouse system. For this purpose the discrete wavelet transform is applied to transform outdoor/indoor climatic signals of a greenhouse. The considered greenhouse is a nonlinear MIMO process with four inputs and two outputs. Results simulation had shown that ANN metrics (mean square error and adaptation time) are improved using Haar wavelet with one decomposition level.
IOSR Journal of Mechanical and Civil Engineering, 2016
The wind tower is an ancient technique used since the time of Feraoun (1300 AC) until today for n... more The wind tower is an ancient technique used since the time of Feraoun (1300 AC) until today for natural ventilation in the arid Middle East region including Iraq and Iran without any energy consumption ensuring thermal comfort and considerable energy efficiency by comparing it with HVAC systems (Heating, Ventilation and AirConditioning) widely used in these areas. Two mechanisms are used in the natural ventilation: buoyancy caused by the temperature difference and the wind pressure forces on the envelope of the ventilated structure. Δp is the pressure difference resulting from the external pressure caused by the interaction wind-structure and the internal pressure which cause an airflow inside building driving by Δp and finally the air leave the building through building openings (doors, windows, etc.). In order to create maximum pressure difference, the wind tower geometry (windward side) is questioned. Four aerodynamic shapes are studied: square, circular, triangular and U. The results show that the circular and triangular models have external and internal pressures much higher than the square and U model. This new aerodynamic geometries are more appropriate to create maximum Δp than rectangular tower. These results confirm the importance of Computational Wind Engineering CWE in the study of natural ventilation potential of this technique especially in windy arid regions such as the South of Algeria. CFD techniques have become increasingly essential as an aid to decision in modern design of natural ventilation systems.
In this paper, we analyze long-term data of solar radiation, spanning a period of 23 years, of th... more In this paper, we analyze long-term data of solar radiation, spanning a period of 23 years, of the town of Adrar located in the western south of Algeria to evaluate technicaleconomic feasibility of using a photovoltaic system. The aim is to answer at load demand of a typical residential house with the annual electric energy demand of 8000kWh, an average calculated according to a study made by the Algerian government and to limit carbon emissions. Simulation results using the Hybrid Optimization Model for Electric Renewable (HOMER) software is proposed. The optimization modeling demonstrates that 100% of power demand can be supplied by a PV configuration composed of 8kW PV system together with battery storage of 37.5h of autonomy. The PV penetration is 146%, the cost of generating energy from the considered PV system has been found to be 0.46 $/kWh. It is shown that with the proposed photovoltaic system, approximately 11 tons/year of the carbon emissions entering the atmosphere can be reduced for one house only.
Numerical Simulation of Thermal Behavior Airflow Facades Building in Arid Zone
International Journal of Civil Engineering
Environmental evaluation of typical house situated in the south of Algeria by using photovoltaic system
2012 2nd International Symposium On Environment Friendly Energies And Applications, 2012
ABSTRACT In this paper, we analyze long-term data of solar radiation, spanning a period of 23 yea... more ABSTRACT In this paper, we analyze long-term data of solar radiation, spanning a period of 23 years, of the town of Adrar located in the western south of Algeria to evaluate technical-economic feasibility of using a photovoltaic system. The aim is to answer at load demand of a typical residential house with the annual electric energy demand of 8000kWh, an average calculated according to a study made by the Algerian government and to limit carbon emissions. Simulation results using the Hybrid Optimization Model for Electric Renewable (HOMER) software is proposed. The optimization modeling demonstrates that 100% of power demand can be supplied by a PV configuration composed of 8kW PV system together with battery storage of 37.5h of autonomy. The PV penetration is 146%, the cost of generating energy from the considered PV system has been found to be 0.46 $/kWh. It is shown that with the proposed photovoltaic system, approximately 11 tons/year of the carbon emissions entering the atmosphere can be reduced for one house only.
Air Circulation Simulation of Urban Microclimate Interaction with Building in the Case Canyon Street in South West Algeria
International Symposium on Advances in Computational Heat Transfer, 2008
Energy Procedia, 2013
Heat exchange by convection and thermal conduction between the two environments of a building sep... more Heat exchange by convection and thermal conduction between the two environments of a building separated by a vertical wall and double wall air gap are studied numerically. The transfer is twodimensional effect of the external environment the hottest to the internal environment of the building through a facade consisting of two walls separated by a layer of air. The structure of the flow and the temperature distribution in the two media and the temperature profile of the surfaces of the front wall are determined based on the simulation results for the temperature difference (Rayleigh number) and the temperature sinusoidal excitation.
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Papers by Draoui Belkacem