Browsing by Author "Hafaifa, Ahmed"

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    Amélioration de la fiabilité d’un chantier de forage à l’aide des réseaux bayésiens
    (2015) Halimi,Djamel; Hafaifa, Ahmed; Bouali, Elahmoune; Guemana, Mouloud
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    Carbone dioxide capture and utilization in gas turbine plants via the integration of power to gas
    (Elsevier, 2017) Boubenia, Ahmed; Hafaifa, Ahmed; Kouzou, Abdellah
    Recent studies have shown that the concentration of greenhouse gases such as carbon dioxide in the atmosphere is growing rapidly over recent years and this can lead to major dangers for the planet. This growth is mainly due to the emissions from fossil power source such as diesel plants and gas turbines. The purpose of the present paper is to study the feasibility of integrating a technique based on power to gas concept in fossil power plants such as gas turbine. This work is based on the reduction of pollutant gas emissions produced from a gas turbine plant, especially the carbon dioxide. This captured gas (CO2) can be converted once again into energy via the technique of power to gas concept. This concept starts by extracting CO2 from exhaust gases which is carried out by multiple chemical process. On the other side, H2 is produced from water electrolysis using the excess electricity which is produced but not consumed by the existing loads. finally the production of Methane (CH4) can be achieved by combination of the captured CO2 and the extracted H2 via a reactor known as a reactor of Sabatier, this operation is called methanation or hydrogenation of carbon dioxide. Simulation results are presented for the validation of the proposed technique based on real data obtained on site from a gas turbine plant. Copyright © 2016, Southwest Petroleum University. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND
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    Energy and environmental performance analysis of grid-connected photovoltaic systems under similar outdoor conditions in the saharan environment
    (2020) Deriche, Mohammed Amine; Hafaifa, Ahmed; Tahri, Ali; Mohammedi, Kamal; Tahri, Fatima
    The aim of this paper is to present a one-year performance analysis of four grid-connected PV systems installed at Ghardaia city in Algeria’s Sahara. The grid-connected PV systems are based on four different PV module technologies which are: monocrystalline silicon (m-Si), multi-crystalline silicon (mc-Si), cadmium telluride (Cd-Te) and amorphous (a-Si) PV module technologies. The PV systems based on the thin film technologies have their performance ratio better throughout the year when the performance ratio of the mc-Si technology is better in the winter season. The a-Si PV system has its performance ratio about 6.13 % more better than mc-Si and 8.90 % better than m-Si. The AC energy produced with the a-Si PV system is 13.32 % more than what the mc-Si system produces. It was found that the a-Si PV system performs better than the other technologies under the Saharan climate conditions of Ghardaia city. The energy payback time (EPBT) and greenhouse gases (GHG) emissions of the different PV systems were analyzed. The EPBT and GHG emissions per year, vary from a minimum value of 2.8 years to a maximum value of 5.73 years and from 13.24 tons to 32.03 tons of CO2/kWh for CdTe and m-Si respectively. The CdTe PV system performs better in terms of EPBT and GHG emissions compared to the other technologies (m-Si, mc-Si and a-Si) due to its low life cycle energy requirement.
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    Etude de fiabilité à base des techniques de l’intelligence artificielle : application par les réseaux bayésiens
    (2013) Halimi,Djamel; Hafaifa, Ahmed; Bouali, Elahmoune; Guemana, Mouloud
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    Modeling of a Small Scale Wind Turbine for Water Pumping Process: case study
    (L&H Scientific Publishing, 2018) Boubenia, Ahmed; Hafaifa, Ahmed; Guemana, Mouloud; Kouzou, Abdellah; Becherif, Mohamed
    This paper deals with the study of a small scale wind turbine implementation for agricultural isolated location. Indeed, the electrification of these locations for industrial and agricultural requirements remains one of the largest current projects, especially when dealing with the use of sustainable sources such as solar, hydro and wind power. The main aim of this work is to validate the feasibility of using wind turbine in this location and to evaluate the performance of the excess energy storage capacity, which in this case is stored as water under the potential energy form. The study represented in this paper has been performed under the case of pumping water station using wind turbine in an isolated location at the north of Algeria, considering that this site fulfills the requirement of a favorable wind potential and a permanent water source. The design of the used wind turbine is based on the constraints of the climate data of the selected location and the lower cost of the implementation means, whereas, the water tank dimensions are is optimized with respect to the daily water consumption data and the available excess of energy to be stored and to be used later for water pumping during the period of wind absence
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    Modélisation et commande d'un système de compression par logique floue : Application au phénomème de pompage
    (2004) Hafaifa, Ahmed
    Il y ‘a encore quelques années, les gaz associes étaient évacués vers les torches étant donné que la structure de récupération de ces gaz n’était pas économiquement rentable. L’installation de stations de réinjection, comme c’est le cas à Hassi Messaoud avec l’avènement de certaines machines pouvant traiter des quantités énormes de gaz, nous permet non seulement de récupérer ces gaz mais aussi d’augmenter la production du brut. Cette technique de réinjection du gaz à haute pression permet de réinjecter les gaz dans les puits ou gisements et permet de donner un mélange gaz – brut à haute pression et fait croître les coefficients d’exploitation du gisement. Les machines qui se sont avérées les plus indiquées sont les compresseurs. Néanmoins, ces machines sont soumis à un problèmes très important à savoir le phénomène de pompage qui est un état d’instabilité de fonctionnement entraînant des pulsations pouvant être dangereuses pour leur tenue mécanique provoquant l’inversion de la poussée axiale du rotor, des vibrations au niveau du compresseur et la rupture des ailettes suite à l’inversion du débit. Il est donc essentiel de maintenir le fonctionnement du compresseur en dehors de la zone d’instabilité. Ce phénomène apparaît dans les zones de fonctionnement correspondant aux bas débit à l’aspiration et peut généralement avoir lieu à partir du moment où la courbe caractéristique « taux de compression – débit » atteint son maximum. Une diminution du débit d’aspiration engendre une translation de la caractéristique du réseau vers une zone d’instabilité. Une augmentation du volume de refoulement peut entraîner une re – circulation du gaz dans le sens inverse de l’écoulement, ce qui peut créer des vibrations à l’intérieur du compresseur…
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    New approach for a supervisor of the PI controller parameters applied for induction motor
    (2009) Laroussi, Kouider; Hafaifa, Ahmed; Zelmat, Mimoune
    The simplicity of traditional controllers makes of them the popular and the most used solution in the industry of nowadays. However, they suffer from some limitations and can not deal with nonlinear dynamics and system parameters variation. in the literature several strategies of adaptation are developed to alleviate theses limitations. In this paper we propose a combination of two strategies for supervision and adaptation of PI parameters. We apply the obtained structure to the control of induction machine speed
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    A new engineering method for fuzzy reliability analysis of surge control in centrifugal compressor
    (2009) Hafaifa, Ahmed; Laaouad, Ferhat; Guemana, Moulod
    Problem statement: The surge phenomenon in the centrifugal compressor, the nonlinearities and uncertainties of the compression system make it impossible to use a conventional controller over a wide range of operation. Approach: A new dual fuzzy controller for nonlinear model of compression system was proposed in this study. This fuzzy controller was designed that consisted of active surge control and phase control without any explicit system models, but driven in human thinking mechanism. Results: Simulation example of compression system was given to demonstrate the validity of proposed control scheme. It was shown that fuzzy controller can be simplified and good tracking control performance can be achieved by choosing appropriate fuzzy roles. But, the dual fuzzy controller can successfully intervene in control surge of compression system. Conclusion: This new fuzzy control methodology suggested in this study reproduced well main characteristics of turbo compressor dynamic model developed by Moore and Gretzer and give place to a more precise and easy to handle representation. It is about an inaccuracies reproducing with a certain degree of satisfaction of real process without being as much complex
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    Parametric output feedback stabilization in MIMO systems : application to gas turbine power plant
    (IEEE, 2017) Nail, Bachir; Kouzou, Abdellah; Hafaifa, Ahmed; Bekhiti, Belkacem
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    Performance evaluation of A-Si and CdTe solar photovoltaic using energy and exergy analysis
    (Inder Science, 2020) Deriche, Mohammed Amine; Hafaifa, Ahmed; Mohammedi, Kamal
    In the paper, analysis and a comparative study of exergetic performance has been made for amorphous silicon and cadmium telluride solar PV array in Oued N'echou at Ghardaia, Algeria (32°36′2.43″N of latitude; 3°42′6.32″E of longitude). The experimental data of solar radiation, ambient temperature, wind speed, module temperature, DC power (of the inverter of 96kWac) were measured and recorded for a typical day of December (21 December 2015) to evaluate the exergy and energy conversion efficiency. Applying the first law of thermodynamic and the second law of thermodynamic, the energy and exergy analyses for both PV arrays have been carried out. Exergy efficiency of amorphous PV array varied from 4.84% to 6.90% and varied from 6.25% to 10.85% for cadmium telluride during the day. The energy conversion efficiency curve of both PV arrays were found to be below that of exergy efficiency