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The effectiveness of triangular baffles in enhancing heat transfer within corrugated tubes is examined numerically in this study. Two key parameters influencing performance are examined: baffle placement (staggered and aligned) and their angles of attack (0°, 15°, 30°, and 45°). Heat transfer, friction, as well as performance metrics are comprehensively examined and compared for both configurations. The finite element method (FEM) implemented in CFD software COMSOL Multiphysics 6.1 is employed for simulations across a range of Reynolds numbers (100-400). Results reveal significant heat transfer improvements due to the proposed baffle configurations. Notably, aligned baffles with a 30° angle of attack achieve a 43.6% increase the heat transfer when compared to the baffle-free scenario. Staggered baffles with a 15° angle of attack demonstrate a superior 55.3% improvement compared to the baseline. A comprehensive evaluation of performance criteria identifies staggered baffles with a 30° angle of attack as the optimal configuration for maximizing heat transfer within corrugated tubes.

The study analyzes the unique behavior of two-phase flows when incorporating nanofluids containing aluminum trioxide (Al2O3) and copper (Cu) nanoparticles in a vertical channel. The main goal is to investigate the behavior of air-nanofluid mixtures in this setting, with potential implications for industrial and exploration applications. Research in this area could provide valuable insights into the dynamics of these flows and their impact on heat transfer, fluid dynamics, and material science. This study includes an analysis of upwelling dynamics, the effect of fluid characteristics on bubble growth, and the system's thermal efficiency. Using numerical and quantitative visualization techniques, we seek to understand the behavior of these particles at the interface between the liquid and gas phases by integrating Al2O3 and Cu nanoparticles into the VOF approach. Because of their superior thermal conductivity, copper nanoparticles have a higher volumetric density and provide more efficient heat transfer, leading to quick and efficient thermal dissipation. Smaller nanoparticles offer an increased surface area-to-volume ratio, which improves heat transfer capabilities and ensures uniform heat dissipation throughout the material. Consequently, copper nanoparticles emerge as the preferred choice for applications necessitating high thermal transfer and optimal performance. These results significantly impact the design of more efficient heat exchangers and optimize recovery techniques by elucidating the interactions between these nanoparticles and the surrounding fluids. Furthermore, the selection of smaller copper nanoparticles further amplifies thermal transfer, maximizing performance across diverse applications.

Wind tower (catcher) is an old technique used to provide natural ventilation and thermal comfort in arid regions like Iran, and the Middle East. An attempt is made to improve the performance of such techniques by investigating the effects of the windward wall of a traditional wind tower. Four aerodynamic shapes are studied: circular, triangular, U and square shape. Two- and three-dimensional numerical simulations are carried out to examine the internal and external pressure caused by wind in the region of Bechar (South-West of Algeria). The obtained results showed an increase of airflow velocity at the tower outlet connected directly to the ventilated space by 28 and 16% for the circular and triangular models, respectively, and a decrease by 22% for the U-model. The separation flow zone decreased in both circular and triangular models, in comparison with U and square models. These results can improve the efficiency of natural ventilation of traditional and commercial wind towers.

An objective analysis of the wind atlas map of the region of Adrar (Algeria) at a height of 10 meters above ground is essential, in order to classify these velocities according to the Pacific Northwest Laboratory (PNL) classification, and then to develop the separation velocity map. The present work is conducted in the region of Adrar to determine the monthly, seasonal, and annual energy generated by the Whisper200 wind turbine by using the Rayleigh distribution and the wind data recorded every three hours from January 1st, 1961 to December 31st, 2018. From the obtained findings, the northeast region of Adrar is a suitable region for wind applications. The surface of this area is equal to 16587 km², where two sites are located (Kaberten and Aougroute). However, the second PNL class is divided into seven zones. The wind speed in this region (2nd PNL class) is favourable for the setup of isolated wind turbines or hybrid systems. The following cities are located in this region (2nd PNL class): Adrar, Aoulef, Bordj Baji Mokthar, Timaiaouine, Regagne, and Timimoune.

This paper aims to determine the wind potential in two regions of Algeria according to months, seasons, and entire years. An attempt is made to participate to the update of the wind map in this country, by using the collected hourly data during a period of more than thirty years. The Weibull function is employed to perform the wind data analysis. Two regions are considered: Ilizi and Oran, which are located in the southeast and northwest of Algeria, respectively. The values of the Weibull parameters, average power density, and mean velocity are employed to achieve the statistical analysis. At the height of 10 m from the ground, the obtained results revealed that the highest annual average rate of 6.5 m/s occurred at the city of 'Illizi'. It was also found that the city of 'Es-senia' has a middle potential of wind with an annual mean velocity of 3.5m/s. Furthermore, it was observed that the spring season is the most windy season for both regions.