Faculty of technology_PPI

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Artificial bee colony optimization for economic dispatch with valve point effect
(Higher Education Press, 2014-12) Labbi, Yacine; Ben Attous, Djilani; Mahdad, Belkacem
In recent years, various heuristic optimization methods have been proposed to solve economic dispatch (ED) problem in power systems. This paper presents the well-known power system ED problem solution considering valve-point effect by a new optimization algorithm called artificial bee colony (ABC). The proposed approach has been applied to various test systems with incremental fuel cost function, taking into account the valve-point effects. The results show that the proposed approach is efficient and robust when compared with other optimization algorithms reported in literature.
Chemical composition and antioxidant activity of Apis mellifera bee pollen from northwest Algeria
(Journal of Fundamental and Applied Sciences, 2012-12-31) Rebiai, Abdelkrim; Lanez, Touhami
The aim of this study was to assess the nutritional composition and antioxidant activity of bee pollen produced in the North western region of Algeria. The content of total phenolic compounds, flavonoids, and antioxidant activity using the molybdate ion reduction method were determined. The mean contents of phenolic compounds and total flavonoids were 30.46 ± 8.22 mg of GAE.g–1 pollen and 8.92 ± 5.5 mg of RE.g–1 pollen, respectively. High antioxidant activities were found for the molybdate ion reduction method, with values that ranged from 71.95 to 101.5 μg of GAE.g –1 pollen. The bee pollen of Boufarik showed high antioxidant activity probably due to the high content of phenolic compounds present in pollen.
Comparative Analysis of Multiple Linear Regression and Generalized Regression Neural Network for Water Temperature Estimation of Fontaine Des Gazelles Reservoir Dam-Biskra, Algeria
(The International Society for Engineers and Researchers (ISER). Istanbul. Turquie, 2024-02-06) MEZIANI, ASSIA
Our research centers on estimating the water temperature of Fontaine de Gazelles Reservoir Dam by analyzing air temperature, relative humidity, solar radiation, atmospheric pressure, wind speed, and precipitation. These variables collectively impact water temperature, reflecting the thermal environment, water vapor content, solar energy, air density, wind-induced processes, and precipitation cooling. We employ Multiple Linear Regression (MLR) and Generalized Regression Neural Networks (GRNN) models for accurate estimates. MLR captures linear dependencies among climate variables, while GRNN model complex nonlinear relationships. Trained on historical data and real-time measurements, both MLR and GRNN demonstrate strong capabilities. MLR achieves high Nash-Sutcliffe Efficiency (0.991 to 0.997) and low Root Mean Squared Error (0.406 to 0.625), while GRNN achieves similar values. Both models consistently exceed a coefficient of determination R2 equal 0.99, indicating a robust correlation, and display low Mean Absolute Error (0.236 to 0.391), affirming their accuracy. This attests to MLR and GRNN's reliability in estimating water temperature for the Fontaine de Gazelles Reservoir Dam. الملخص (باللغة العربية) تركز بحثنا على تقدير درجة حرارة الماء في سد خزان فونتين دي غازيل المتواجد ببسكرة من خلال تحليل درجة حرارة الهواء والرطوبة النسبية والإشعاع الشمسي والضغط الجوي وسرعة الرياح وهطول الأمطار. تؤثر هذه المتغيرات الجوية بشكل اساسي على درجة حرارة الماء، مما يعكس على البيئة ومياه السد، والطاقة الشمسية، وكثافة الهواء، والعمليات التي تحدثها الرياح، والأمطار. في هذا العمل استخدمنا نموذجين الاول يعتمد على الانحدار الخطي والثاني على الشبكات العصبية للانحدار المعمم. للحصول على تقديرات دقيقة لدرجة حرارة مياه السد. النتائج كانت كتالي يلتقط نموذج الانحدار الخطي التبعيات الخطية بين متغيرات المناخ، في حين تقوم الشبكات العصبية بنمذجة العلاقات غير الخطية المعقدة. ومن خلال تدريبهما على البيانات الجوية والقياسات في الوقت الفعلي، أظهر كل من نموذج الانحدار الخطي والشبكات العصبية تقدرات ممتازة. لدرجات حرارة المياه للسد حيث يحقق نموذج الانحدار الخطي كفاءة عالية (حسب قيم ناش للنموذج يتراوح من 0.991 إلى 0.997) والخطأ التربيعي لمتوسط الجذر المنخفض (0.406 إلى 0.625)، بينما تحقق الشبكات العصبية قيمًا مماثلة. يتجاوز كلا النموذجين باستمرار معامل الارتباط الذي يساوي 0.99، مما يشير إلى وجود ارتباط قوي للمتغيرات، ويعرض متوسط خطأ مطلق منخفض (0.236 إلى 0.391)، مما يؤكد دقتهما. وهذا ياكدعلى فعالية ودقة النموذجين في تقدير درجة حرارة المياه لسد فونتين دي غازيل المتواجد ببسكرة.
Comparative study of hemispherical solar distillers iron-fins
(Elsevier, 2021-04-10) Attia, Mohammed El Hadi; Kabeel, AE; Abdelgaied, Mohamed; El-Maghlany, Wael M; Bellila, Abdelkader
The ratio between surface area to volume is higher in spherical distillers than traditional single slope distillers. To utilize this advantage, the study measures hemispherical distillers performance. Iron fins have been employed at different lengths and spacing in absorber plate to increase absorption area and transmit heat from hot basin plate to saline water. Three configurations have been tested under same operating conditions. First, the conventional hemispherical distiller without fins representing the reference case (CHSS). Second, the modified hemispherical distiller with fins set at 5 cm spacing (MHSS-IF5). Third, the modified hemispherical distiller with fins set at 7 cm (MHSS-IF7). Fins diameter is constant at 1.2 cm with tested length of 3, 2 and 1 cm starting from the basin absorber plate. Basin salt water is fixed at 3 cm (maximum fin length) during experiments. Results prove that fin utilization is important in performance enhancement. However, fin length effect on performance depends on spacing due to shading effect in distillers. Consequently, the fins utilization improves distiller productivity up to 56.73% with best configuration of MHSS-IF7 with 2 cm fin length and 7 cm spacing. The fins utilization is not costly in the hemispherical distiller with positive enhancement contribution leads to minimum cost per liter of produced water.
Comparative Study of Honey Collected from Different Flora of Algeria
(Journal of Fundamental and Applied Sciences, 2014) Rebiai, A; Lanez, T
The aim of the present study was to evaluate the physical and chemical properties of five Algerian unifloral types of honey. Several physical parameters of honey, such as pH, moisture content, electrical conductivity, total dissolved solids, color intensity and total sugar content, were measured. The mean pH, moisture content, EC and water insoluble solids of Algerian honey were 4.41± 0.58, 15.3 ± 1.5%, 0.324± 0.116 mS/cm and 0.141± 0.065%, respectively. The mean color was 81 ± 72 mm Pfund. The majority of honey samples test results (moisture content, electric conductivity and acidity) levels were within the acceptable range of world honey standards.
A comparative study on structural and optical properties of ZnO and Al-doped ZnO thin films obtained by ultrasonic spray method using different solvents
(Urban & Fischer, 2014-07-01) Gahtar, Abdelouahab; Rahal, Achour; Benhaoua, Boubaker; Benramache, Said
Abstract Transparent conducting ZnO and Al doped ZnO thin films were deposited on glass substrate by ultrasonic spray method. The thin films with concentration of 0.1 M were deposited at 350 °C with 2 min of deposition time. The effects of ethanol and methanol solution before and after doping on the structural, optical and electrical properties were examined. The DRX analyses indicated that ZnO films have nanocrystalline nature and hexagonal wurtzite structure with (1 0 0) and (0 0 2) preferential orientation corresponding to ZnO films resulting from methanol and ethanol solution, respectively. The crystallinity of the thin films improved with methanol solution after doping to (0 0 2) oriented. All films exhibit an average optical transparency about 90%, in the visible range. The band gaps values of ZnO thin films are increased after doping from 3.10 to 3.26 eV and 3.27 to 3.30 eV upon Al doping obtained by ethanol and methanol solution, respectively. The electrical conductivity increase from 7.5 to 15.2 (Ω cm)−1 of undoped to Al doped ZnO thin films prepared by using ethanol solution. However, for the methanol solution; the electrical conductivity of the film is stabilized after doping.
Comparison Study Between SVM and PWM Inverter in Sliding Mode Control of Active and Reactive Power Control of a DFIG for Variable Speed Wind Energy
(İlhami ÇOLAK, 2012-09-18) Bekakra, Youcef; Ben Attous, Djilani
t- In this paper, we present a comparative study between space vector modulation (SVM) and pulse width modulation (PWM) inverter in sliding mode control (SMC) of active and reactive power control of a doubly fed induction generator (DFIG) for variable speed wind energy. The feasibility and effectiveness of the two methods are demonstrated by simulation results. The obtained results showed that, the proposed SMC with SVM inverter have stator and rotor current with low harmonic distortion and low active and reactive powers ripples than PWM inverter.
Control of methane flame properties by hydrogen fuel addition: Application to power plant combustion chamber
(Pergamon, 2017-03-30) Bouras, Fethi; Attia, Mohammed El Hadi; Khaldi, Fouad; Si-Ameur, Mohammed
This study presents a numerical investigation of the effects of mixing methane/hydrogen on turbulent combustion processes taking place in a burner similar to that integrated in gas turbine power plants. Thereby, in comparison to the reference case where the burner is fuelled by 100% of methane, the variations of the axial velocity field, temperature field and mass fraction of carbon monoxide field are examined for different percentages of hydrogen fuel injection. The computed results, obtained by using the software Fluent-CFD, are compared and validated against experimental reference data. Results show that the hydrogen addition to the methane has an impact on all physical and chemical parameters of the reactive system
Doubly-fed induction generator drive based WECS using fuzzy logic controller
(Higher Education Press, 2015-09) Dida, Abdelhak; Ben Attous, Djilani
The purpose of this paper is to improve the control performance of the variable speed, constant frequency doubly-fed induction generator in the wind turbine generation system by using fuzzy logic controllers. The control of the rotor-side converter is realized by stator flux oriented control, whereas the control of the grid-side converter is performed by a control strategy based on grid voltage orientation to maintain the DC-link voltage stability. An intelligent fuzzy inference system is proposed as an alternative of the conventional proportional and integral (PI) controller to overcome any disturbance, such as fast wind speed variation, short grid voltage fault, parameter variations and so on. Five fuzzy logic controllers are used in the rotor side converter (RSC) for maximum power point tracking (MPPT) algorithm, active and reactive power control loops, and another two fuzzy logic controllers for direct and quadratic rotor currents components control loops. The performances have been tested on 1.5 MW doubly-fed induction generator (DFIG) in a Matlab/Simulink software environment.
Effect of aluminum balls on the productivity of solar distillate
(Elsevier, 2020-08-01) Attia, Mohammed El Hadi; Driss, Zied; Manokar, A Muthu; Sathyamurthy, Ravishankar
Drinking water has become a real global problem, despite the abundance of unsaturated saltwater and colorless, which do not meet the requirements of the World Health Organization. The El Oued, in the southeastern part of Algeria, contains vast quantities of salt water and non-potable water. Solar distillation can be used as a solution to resolve this trouble. To provide drinking water, we use free sunlight to treat salt water. The traditional solar distillation device, which is one mile long (0.5×0.5 m), is designed to confirm the effectiveness of this solution. The traditional single slope solar distillation, its dimensions (0.5×0.5 m), is designed to confirm the effectiveness of this solution. Solar distillation is an environmental, economic and simple technique, but it needs some modifications to increase the distilled water production. In this work, we added aluminum balls inside the solar distillate box. In this work, we added 42 aluminum balls with a diameter of 2 cm inside a solar distillates box; positioned as follows (6 balls x 7 balls). The results showed that aluminum balls increased the distillation of distilled water by about 27.16 %.
Effect of Extraction Methods on Polyphenols, Flavonoids, Mineral Elements, and Biological Activities of Essential Oil and Extracts of Mentha pulegium L
(MDPI, 2021-12-21) Messaoudi, Mohammed; Rebiai, Abdelkrim; Sawicka, Barbara; Atanassova, Maria; Ouakouak, Hamza; Larkem, Imane; Egbuna, Chukwuebuka
ur study evaluated the in vitro antioxidant properties, antibacterial and antifungal activities, anti-inflammatory properties, and chemical composition of the essential oils (EOs), total phenol, and total flavonoid of wild Mentha pulegium L. This study also determined the mineral (nutritional and toxic) elements in the plant. The EOs were extracted using three techniques—hydro distillation (HD), steam distillation (SD), and microwave-assisted distillation (MAD)—and were analyzed using chromatography coupled with flame ionization (GC-FID) and gas chromatography attached with mass spectrometry detector (GC-MS). The antioxidant effects of the EOs were tested with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), while the antibacterial and antifungal activities of the EO and methanolic extract were tested using Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Twenty-six compounds were identified in the essential oil, representing 97.73% of the total oil, with 0.202% yield. The major components were pulegone (74.81%), menthone (13.01%) and piperitone (3.82%). Twenty-one elements, including macro- and micro-elements (Ba, Br, Ca, Cl, Co, Cr, Cs, Eu, Fe, K, Mg, Mn, Mo, Na, Rb, Sb, Sc, Sr, Th, U and Zn), were detected using neutron activation analysis (INAA) and inductively coupled plasma optical emission spectrometry (ICP-OES), with the concentration of mineral element close to the FAO recommendation. The results show that the EOs and extracts from Mentha pulegium L. had significant antimicrobial activities against the microorganisms, including five human pathogenic bacteria, one yeast (Candida albicans), and one phytopathogenic fungi. The in vivo anti-inflammatory activities of the leaf extracts were confirmed. The results indicate that the EOs and extracts from Mentha pulegium L. have promising applications in the pharmaceutical industries, clinical applications, and in medical research.
Effect of fluorine doping on the structural, optical and electrical properties of SnO2 thin films prepared by spray ultrasonic
(Superlattices and Microstructures, 2014-06) Benhaoua, Atmane; Rahal, Achour; Benhaoua, Boubaker; Jlassi, Mohamed
Abstract The undoped and fluorine doped tin oxide (SnO2) thin films are synthesized by using cost-effective spray ultrasonic technique; the films are sprayed on heated glass substrates at 480 °C. The dependence of structural, optical and electrical properties of SnO2 films on the concentration of fluorine is investigated. X-ray diffraction, Optical absorption, four-point probe and Hall Effect studies have been performed on undoped and fluorine doped SnO2 (FTO) films. X-ray diffraction pattern reveals the presence of cassiterite structure with (2 0 0) as preferential orientation for FTO films. The crystallite size varies from 10.3 to 27.12 nm and was affected by F concentration which was lying between 0 and 12 wt.%. All films exhibit optical transmission T(λ) more than 83.9% in visible region; the optically estimated film thickness varies from 700 to 975 nm for the same given time (3 min deposition) and band gap (Eg) varies from 3.651 to 3.902 eV. The electrical study reveals that the films have n-type electrical conductivity and depend upon fluorine concentration too. The sprayed FTO film doped at 6 wt.% has the minimum resistivity of 1.47 × 10−3 Ω cm and minimum resistance sheet (Rsh) of 21 Ω/cm2 whereas the carrier concentration and mobility were about 2.04 × 1019 cm−3 and 208.4 cm2 V−1 s−1 respectively.
Effect of substrate temperature on the stability of transparent conducting cobalt doped ZnO thin films
(IOP Publishing, 2012-09-01) Benramache, Said; Benhaoua, Boubaker; Chabane, Foued
Transparent conducting Co doped ZnO thin films have been fabricated by Ultrasonic spray. The thin films were deposited at three different substrate temperatures of 300, 350 and 400 ℃. The obtained films had a hexagonal wurtzite structure with a strong (002) preferred orientation. The maximum crystallite size value of the film deposited at 350 ℃ is 55.46 nm. Spectrophotometer (UV-vis) of a Co doped ZnO film deposited at 350 ℃ shows an average transmittance of about 90%. The band gap energy increased from 3.351 to 3.362 eV when the substrate temperature increased from 300 to 350 ℃. The electrical conductivity of the films deposited at 300, 350 and 400 ℃ were 7.424, 7.547 and 6.743 (Ω·cm)-1 respectively. The maximum activation energy value of the films at 350 ℃ was 1.28 eV, indicating that the films exhibit a n-type semiconducting nature.
The effects of solvent nature on spray-deposited ZnO thin film prepared from Zn (CH3COO)2, 2H2O
(Urban & Fischer, 2014-01-01) Benramache, Said; Rahal, Achour; Benhaoua, Boubaker
Transparent conducting zinc oxide was deposited on glass substrate by ultrasonic spray method. The ZnO samples with concentration of 0.1 M were deposited at 300, 350 and 400 °C with 2 min of deposition time. The effects of substrate temperature, ethanol and methanol solution on the structural, electrical and optical properties were examined. The DRX analyses indicated that ZnO films have polycrystalline nature and hexagonal wurtzite structure with (1 0 0) and (0 0 2) preferential orientation corresponding to ZnO films resulting from methanol and ethanol, respectively. The crystallinity of the thin films improved with ethanol solution. All films exhibit an average optical transparency about 80%, in the visible range. The band gap energy of ZnO films obtained with methanol solution higher than of ethanol solution for all the films. The electrical resistivity decrease with ZnO obtained from ethanol indicated; due to the maximum crystallite size retched at this point.
Effects of speech codecs on a remote speaker recognition system using noval SAD
(University of Eloued جامعة الوادي, 2014-04-02) Ajgou, Ridh; Sbaa, Salim; Ghendir, Said; Chamsa, Ali; Taleb- Ahmed, A.
This paper deals with the effects of speech codecs on remote texit-independent speaker recognition performance in VoIPapplications, considering three types of speech codec: PCM, DPCM and ADPCM conforming to International Telecommunications Union-Telecoms (ITU-T) recommendation used in telephony and VoIP (Voice over Internet Protocol). In order to improve the speaker recognition performance in noisy environment we propose a new robust speech activity detection algorithm (SAD) using "Adaptive Threshold", which can be simulated with speech wave files of TIMIT database submerged in an additive noise. Moreover, the speaker recognition system is based on Vector Quantization and Mel-Frequency Cepstral features extraction algorithm. Where, the feature extraction proceed after (for testing phase) and before (for training phase ) the speech is sending over communication channel. Therefore, the digital channels can introduce several types of degradation. To overcome the degradation of channel, a convolutional code is used as error-control coding with the AWGN channel, Finely, the best overall performance of speech codecs was observed for the PCM code in terùs of recognition rate accuracy and execution time.
Elaboration and characterisation of ZnO thin films
(EDP Sciences, 2012) Benramache, S.; Benhaoua, B.; Khechai, N.; Chabane, F.
Abstract – Highly transparent ZnO thin films have been prepared on microscope glass substrate using dip-coating technique. The films were obtained at a concentration of solgel solution is 0.5 M. The structural and optical properties of the ZnO thin films were studied as a function of the annealing temperature varying between 450 to 600 ◦C. From the XRD analysis, the whole obtained films have a hexagonal wurtzite structure with a strong (002) preferred c-axis orientation. The grain size increased with annealing temperature indicating an improvement in the crystallinity of the films. The average transmittance of all the films is about 70–80% as measured by UV-vis analyzer. The band gap increased with the increase of temperature from 3.25 to 3.42 eV. The decrease of the strain of ZnO films is probably due to an improvement of the crystallinity of the films. The best result is achieved at 600 ◦C.
Enhanced photocatalytic and antiviral activities of CuO@Fe2O3 NC for amoxicillin degradation and SARS-COV-2 treatment
(University of Eloued جامعة الوادي, 2023-12-07) Laouini, Salah Eddine; Legmairi, Souheila; Meneceur, Souhaila; Hasan, Gamil Gamal; Hamdi, Ali Mohammed
Copper oxide nanoparticles (CuO NPs) and CuO NPs decorated with hematite (Fe2O3) nanocomposites (CuO@Fe2O3 NC) were biosynthesized by a green method using Portulaca oleracea leaves extract. The NC were characterized using various techniques, including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and UV-Vis spectroscopy. The results showed that the synthesized CuO and CuO@Fe2O3 NC were crystalline with a monoclinic crystal structure and contained functional groups responsible for catalytic activity. The size of the nanocomposites ranged from 39.5 to 45.9 nm, and they exhibited a variety of agglomerated or aggregated shapes. The CuO@Fe2O3 NC showed improved photocatalytic activity for the degradation of antibiotics in water and wastewater and promising antiviral activity against SARS-CoV-2, indicating its potential for use in disinfection applications. The study investigated the impact of irradiation time on the photocatalytic degradation of Amoxicillin and found that increasing the irradiation time led to a higher degradation rate. The band gap energy (Eg) for pure CuO NPs was around 2.4 eV and dropped to 1.6 eV with CuO@Fe2O3 NC. In summary, the CuO@Fe2O3 NC has the potential to be an efficient photocatalyst and promising antiviral agent for environmental remediation. The CuO@Fe2O3 nanocomposites have been found to possess a high degree of efficacy in inactivating SARS-CoV-2 infectivity. The results of the study indicate that the nanocomposites exhibit potent anti-viral properties and hold significant potential for use in mitigating the spread of the virus الملخص تم تصنيع الجسيمات النانوية لأكسيد النحاس (CuO NPs) وCuO NPs المزينة بمركبات نانوية من الهيماتيت (Fe2O3) (CuO@Fe2O3 NC) بطريقة خضراء باستخدام مستخلص أوراق Portulaca oleracea. تم تشخيص NC باستخدام تقنيات مختلفة، بما في ذلك حيود الأشعة السينية (XRD)، والتحليل الطيفي للأشعة تحت الحمراء (FTIR) لتحويل فورييه، والمجهر الإلكتروني الماسح (SEM)، والتحليل الطيفي للأشعة السينية المشتتة من الطاقة (EDS)، والتحليل الطيفي للأشعة فوق البنفسجية. أظهرت النتائج أن CuO وCuO@Fe2O3 NC المُصنّعين كانا بلوريين بتركيب بلوري أحادي الميل ويحتويان على مجموعات وظيفية مسؤولة عن النشاط التحفيزي. تراوح حجم المركبات النانوية من 39.5 إلى 45.9 نانومتر، وأظهرت مجموعة متنوعة من الأشكال المتكتلة أو المجمعة. أظهر CuO@Fe2O3 NC نشاط تحفيز ضوئي محسّن لتحلل المضادات الحيوية في الماء ومياه الصرف الصحي ونشاطًا واعدًا مضادًا للفيروسات ضد SARS-CoV-2، مما يشير إلى إمكانية استخدامه في تطبيقات التطهير. بحثت الدراسة في تأثير وقت التشعيع على التحلل الضوئي للأموكسيسيلين ووجدت أن زيادة وقت التشعيع أدى إلى ارتفاع معدل التحلل. كانت طاقة فجوة النطاق (على سبيل المثال) لـ CuO NPs النقية حوالي 2.4 فولت وانخفضت إلى 1.6 فولت مع CuO@Fe2O3 NC. باختصار، يتمتع CuO@Fe2O3 NC بالقدرة على أن يكون محفزًا ضوئيًا فعالًا وعاملًا واعدًا مضادًا للفيروسات للمعالجة البيئية. تم العثور على أن المركبات النانوية CuO@Fe2O3 تمتلك درجة عالية من الفعالية في تعطيل عدوى SARS-CoV-2. تشير نتائج الدراسة إلى أن المركبات النانوية تظهر خصائص قوية مضادة للفيروسات ولها إمكانات كبيرة للاستخدام في التخفيف من انتشار الفيروس
Enhancement of hemispherical solar still productivity using iron, zinc and copper trays
(Pergamon, 2021-03-01) Attia, Mohammed El Hadi; AE, Kabeel; Abdelgaied, Mohamed; FA, Essa; ZM, Omara
In this manuscript, a hemispherical solar still with different metal trays (copper, zinc, and iron) painted with black was studied experimentally. Four hemispherical solar stills were manufactured; the first is the conventional hemispherical solar still which represent the reference case (CHSS), the second, third and fourth were the modified hemispherical solar stills with adding black metal trays of copper, zinc, and iron, respectively. These trays were placed at the bottom of the distiller basin. This modification led to a significant increase in the rate of evaporation of the salt water in the distiller basin due to the improved heat transfer characteristics. The basin water depth in the trays are kept constant at 10 mm in all experiments. The results showed that the accumulative yield of the hemispherical solar still reached to 4.8 kg/m2/day, while the utilization of iron, zinc and copper trays improved the accumulative yield to 5.5, 6.3 and 7.35 kg/m2/day, respectively. These results presented that the trays hemispherical solar still of iron (THSSI) was about 1.17 times the daily productivity of CHSS, while trays hemispherical solar still of zinc (THSSZ) showed an increase in productivity by 31.25% compared to CHSS. Moreover, the trays hemispherical solar still of copper (THSSC) gave improved productivity by 53.125% compared to CHSS. The thermal efficiency of CHSS, THSSI, THSSZ and THSSC were 37.4%, 42.8%, 49% and 57.2%, respectively.
Enhancing the solar still output using micro/nano-particles of aluminum oxide at different concentrations: An experimental study, energy, exergy and economic analysis
(Elsevier, 2021-09-01) Benoudina, Belkheir; Attia, Mohammed El Hadi; Driss, Zied; Afzal, Asif; Manokar, A Muthu; Sathyamurthy, Ravishankar
In this work, the use of micro/Nano-particles of aluminum oxide (Al2O3) with various concentrations in solar still has been reported. Three solar distillers has been fabricated and tested: first distiller is a Conventional Solar Still (CSS), the second distiller is a Modified Solar Still (MSS) contains micro-particles of Al2O3 (MSS – 0.1, 0.2 and 0.3% MP of Al2O3) and the third distiller is a MSS contains Nano-particles of Al2O3 (MSS – 0.1, 0.2 and 0.3% NP of Al2O3). In this experimental study, the micro/Nano-particles of the Al2O3 concentrations are prepared at the concentration ratio of 0.1, 0.2 and 0.3%. From the experimental outputs by adding Nano-particles of Al2O3 with concentrations of 0.1%, 0.2% and 0.3% in the CSS, the productivity of 4.9, 5.47 and 6.12 L/m2 has been observed. However, when using the micro-particles of Al2O3, the MSS productivity is equal to 4.07, 4.54 and 4.96 L/m2 for the concentrations equal to 0.1, 0.2 and 0.3%, respectively. While the maximum productivity of the CSS without micro/Nano-particles of Al2O3 was 3.02 L/m2 . Furthermore, the daily increase in yield of 62.25, 81.12 and 102.64% are obtained when using the Nano-particles of Al2O3 with the concentrations of 0.1, 0.2 and 0.3% respectively, as compared to the CSS. By using the micro-particles of Al2O3, the daily increase reaches only 34.77, 50.33 and 64.24% for the concentration equal to 0.1%, 0.2% and 0.3%, respectively as compared to the CSS.
Experimental study of a direct solar drying process with a thermal storage System using latent heat
(Sousse - Tunisia, 2024-12-22) ZINE, Ali; BENSEDDIK, Abdelouahab; SAIM, Rachid; LAOUINI, Abdeldjalil; OUCIF KHALED, M Tayeb
In this study, we designed a direct solar dryer at the Research and Development Unit for Renewable Energies in Ghardaia to dry tomatoes. A phase change material was used to store excess heat and utilize it when the sun was absent to increase the dryer's efficiency. The obtained results from the drying kinetics were modeled. The results showed that the Page model was the best model to predict the drying kinetics of tomatoes in the studied dryer (𝑅2=0.99946,𝑀𝑆𝐸=0.00911,𝜒=8.2914𝐸−5 ). Additionally, the use of the phase change material increased the dryer’s temperature in the absence of sunlight compared to the dryer without the phase change material. The effective moisture diffusion value in the tomato slices was 5.12586−9(𝑚2𝑠⁄). الملخص قمنا في هذه الدراسة بتصميم مجفف شمسي مباشر بوحدة البحث والتطوير للطاقات المتجددة بغرداية لتجفيف الطماطم. تم استخدام مادة متغيرة الطور لتخزين الحرارة الزائدة واستخدامها عند غياب الشمس لزيادة كفاءة المجفف. تم نمذجة النتائج التي تم الحصول عليها من حركية التجفيف. أظهرت النتائج أن نموذج بيج هو النموذج الأفضل للتنبؤ بحركية تجفيف الطماطم في المجفف المدروس

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