Energy
Z. Aouissi; F. Chabane; M. S. Teguia
Abstract
The study shows an experimental investigation for a solar air collector with a single pass by adding rectangular baffles for different positions inside the channel. The aim of this study is to improve the thermal efficiency for this collector, and that through testing four cases of baffles positions ...
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The study shows an experimental investigation for a solar air collector with a single pass by adding rectangular baffles for different positions inside the channel. The aim of this study is to improve the thermal efficiency for this collector, and that through testing four cases of baffles positions (mode 1, 2, 3, 4). The study was done under different operating conditions by changing the mass flow rates and positions of baffles. The results show the effectiveness of the baffles in improving the efficiency of the collector, The study also proved that the baffles positions affect thermal efficiency, where the greatest efficiency was recorded in the fourth mode and then in the positioning of obstacles at the middle of the channel for the mode 2 and the mode 4 with a percentage of 76.61 and 90.9, at mass flow rate m=0.0522 kg/s, while the pressure drop was very high in the mode 4, and after that the mode 2. Through the conditions of the study and taking into account all the results; we can say that the best case was mode 2.
Energy
F. Chabane; N. Moummi; C. Toumi; S. Boultif; A. Hecini
Abstract
This study aimed to compare global solar radiation on the horizontal area between two models of Chabane Foued and M.Capderou. The model of Chabane has been interested in pollution factors such as TL (turbidity), BE (Angstraon), and the chemical components of the air such as WV, O3, CH4, CO, CO2, and ...
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This study aimed to compare global solar radiation on the horizontal area between two models of Chabane Foued and M.Capderou. The model of Chabane has been interested in pollution factors such as TL (turbidity), BE (Angstraon), and the chemical components of the air such as WV, O3, CH4, CO, CO2, and the especial part the new pollution factor such as hbeam, kbeam, and kdiffuse, which all influenced onto solar radiation, and the model of Capderou has been used the atmospheric disturbance to calculate the direct and diffuse components of radiation received on a plane, while the constituents of the atmosphere (absorption and diffusion) can be expressed by disturbance factors, which is very necessary to determine irradiation In the clear sky. The results reveal a significant difference between the two models with approximated curves. The difference between the models probably returns to the nature of the geographic site which the authors used and injected into the models.
Chemical Engineering
Z. Aouissi; F. Chabane; M. S. Teguia; N. Belghar; N. Moummi; A. Brima
Abstract
This numerical and experimental work aims to improve the heat transfer inside a solar thermal collector. By incorporating rectangular baffles in the middle of the distributed air passing channel at different angles of inclination (ß= 90°, ß= 180°, ß= 180° and ß= 90°). ...
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This numerical and experimental work aims to improve the heat transfer inside a solar thermal collector. By incorporating rectangular baffles in the middle of the distributed air passing channel at different angles of inclination (ß= 90°, ß= 180°, ß= 180° and ß= 90°). That is called the model H. These experiments were carried out in the Biskra region of Algeria in good natural conditions with an average solar radiation approximately constant I= 869 W/m2 varying from 11:30 to 14:00. After the completion of the experimental investigation, a computational fluid dynamics (CFD) model was created that matches this experimental model with the same experimental boundary conditions. In the numerical study, ANSYS Fluent 18.1 was used to conduct simulations and compare the results of the thermal and hydraulic performance of the collector. It was concluded that the effectiveness of the CFD model, meaning that the theoretical and numerical data were very close to each other for all mass flow rates. As the mass flow increased the heat transfer process increased, while the absorber plate temperature inside the collector for experimental and numerical studies decreased. Addition of baffles increased heat transfer, due to the creation of turbulent flow that leads to crack the dead thermal layers near the absorber plate, which leads to an increase in heat transfer from the absorber plate to the air.
F. Chabane; A. Arif; N. Moummi; A. Brima
Abstract
The dependencye of aerosol optical depth on wavelength as well as the fit of the humidity, temperature and pressure approximation under atmoshperic condition at Biskra city of Algeria has been investigated. Our work consists of measuring and modeling solar radiation on the horizontal area to create a ...
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The dependencye of aerosol optical depth on wavelength as well as the fit of the humidity, temperature and pressure approximation under atmoshperic condition at Biskra city of Algeria has been investigated. Our work consists of measuring and modeling solar radiation on the horizontal area to create a mathematical model of global solar radiation which depends on the aerosol optical depth data between two wavelengths: 550 and 1250 nm. Simultaneous measurements of global solar radiation were carried out and recorded on the horizontal zone on an urban site (Biskra, Algeria) to characterize the radiative effect of atmospheric aerosols from January to December 2013. In addition, the effect of meteorological parameters such as: humidity, ambient temperature, and time durations were studied. This relationship constitutes an alternative tool to estimate AOD at the routine lighting measurements available at many radiometric stations around the world. Finally, a comparative study was established between the theoretical results and the experimental data which leads at an excellent correlation by a low relative error which is limited by the interval 2 and 15%.
F. Chabane; E. Sekseff
Abstract
Our work an experimental study of a double-glazed solar air collector in the BISKRA site. The main objective of our work minimized thermal losses forward. The experimental model used is based on the addition of second glass and the increase in distance between the two panes. The study was carried out ...
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Our work an experimental study of a double-glazed solar air collector in the BISKRA site. The main objective of our work minimized thermal losses forward. The experimental model used is based on the addition of second glass and the increase in distance between the two panes. The study was carried out for the comparison between the average absorber temperature, glass and the outlet temperature and the efficiency for the single-pane and double-pane solar air collector with variable distance (1cm, 2cm and 3cm). Correspond to the three flow rates used. Experimental results show that the addition of second pane is effective in minimizing forward thermal losses for a solar air collector. The results obtained from the experimental readings show that the minimization of thermal losses forward is a very important factor for improving the performance of a solar collector. Experimental results show that the addition of second glazes is effective in minimizing forward thermal losses for a solar air collector.
