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The Reynolds Number Test Bench is a self-contained device that uses water to allow students to study laminar, turbulent flow regimes, and transition conditions. The vertical test bench does not allow a large number of students to see the experiment clearly, it only takes two people in front of the device to block the view of the rest of the students and this causes a problem. The idea of this work is to build a horizontal test bed that allows students to see the experience clearly and easily. The results obtained from our horizontal device are the same as that of the vertical bench.

This work aimed to contribute to studies on the elaboration and implementation of proposals for didactic activity based on an investigative experiment. The work describes an experiment for academic purposes to determine the specific mass and dynamic viscosity of a fluid using the Stokes Method, a simple and low-cost experimental procedure that enables the teaching/learning process of different concepts in the area of Fluid Mechanics, applied to the field of Engineering. The values obtained for specific mass - (899.60 ± 18.00) kg/m3, (996.00 ± 19.93) kg/m3, and (1,298.00 ± 25.97) kg/m3 - and dynamic viscosity - (0.080 ± 0.001) Pa.s, (0.649 ± 0.007) Pa.s, and (0.885 ± 0.015) Pa.s - respectively for the fluids refined soy vegetable oil, detergent and glycerin were close to the values found in the literature and showed a low degree of propagated uncertainty. The development of this implementation was carried out with the support of the EES software and it is presented as a proposal for a didactic activity based on an investigative experiment in Fluid Mechanics. Este trabajo tuvo como objetivo contribuir a los estudios sobre la elaboración e implementación de propuestas de actividad didáctica a partir de un experimento investigativo. El trabajo describe un experimento con fines académicos para determinar la masa específica y la viscosidad dinámica de un fluido utilizando el Método de Stokes, un procedimiento experimental sencillo y de bajo costo que posibilita el proceso de enseñanza/aprendizaje de diferentes conceptos del área. de Mecánica de Fluidos, aplicada al campo de la Ingeniería. Los valores obtenidos de masa específica - (899,60 ± 18,00) kg/m3, (996,00 ± 19,93) kg/m3, y (1.298,00 ± 25,97) kg/m3 - y viscosidad dinámica - (0,080 ± 0,001) Pa.s, (0,649 ± 0,007) Pa.s, y (0,885 ± 0,015) Pa.s - respectivamente para los fluidos aceite vegetal de soya refinado, detergente y glicerina se acercaron a los valores encontrados en la literatura y mostraron un bajo grado de incertidumbre propagada . El desarrollo de esta implementación se realizó con el apoyo del software EES y se presenta como una propuesta de actividad didáctica basada en un experimento investigativo en Mecánica de Fluidos. Este trabalho teve como objetivo contribuir com estudos sobre a elaboração e a implementação de propostas de atividade didática baseada em experimento de cunho investigativo. O trabalho descreve um experimento com fins acadêmicos para a determinação da massa específica e da viscosidade dinâmica de um fluido por meio do Método de Stokes, um procedimento experimental simples e de baixo custo e que possibilita o processo de ensino/aprendizagem de conceitos diversos da área de Mecânica dos Fluidos, aplicada ao campo da Engenharia. Os valores obtidos de massa específica - (899,60 ± 18,00) kg/m3, (996,00 ± 19,93) kg/m3 e (1.298,00 ± 25,97) kg/m3 - e da viscosidade dinâmica - (0,080 ± 0,001) Pa.s, (0,649 ± 0,007) Pa.s e (0,885 ± 0,015) Pa.s, respectivamente para os fluidos óleo vegetal refinado de soja, detergente e glicerina foram próximos dos valores encontrados na literatura e apresentaram baixo grau de incerteza propagada. O desenvolvimento desta implementação foi realizado com apoio do software EES e apresenta-se como uma proposta de atividade didática baseada em experimento de cunho investigativo em Mecânica dos Fluidos.

A wind turbine is a machine that converts the kinetic energy of wind into mechanical energy like wind turbines. This mechanical wind power has been used through the ages to pump water or grind grain. Current machines are used to produce wind-type electricity which is consumed locally (isolated sites), or injected into the electricity network (wind turbines connected to the network). In this work, we are only interested in the modelling of a three-bladed horizontal axis wind turbine. All the models were developed by the Matlab/Simulink software, which makes it possible to set up fairly quickly models as well as the associated. The results revealed that the wind profile ranges between 6-7 (m/s), the power coefficient Cp for a pitch angle of =2 has an average value of 0.54 with a relative speed λ value of 6.40, and when the origin of electrical losses is ignored, the electrical power equals the electromagnetic power, and the mechanical speed is stable between (70-80 rd/s).

Polystyrene is one of the many novel materials being developed today. The goal of our research is to demonstrate that polystyrene is a good construction material in the El Oued region of Southeast Algeria. It can also be a strong rival for other building materials like brick. The results of our research, particularly in thermal testing, are very promising. Polystyrene is a better insulator than brick; the temperature of the polystyrene chamber varies between 26 and 27°C, whereas the temperature of the brick chamber varies between 36 and 37 °C. Polystyrene has a 5 times mechanical impact compared to brick. Despite its lack of availability in the region's markets, polystyrene is a strong rival to other materials such as brick.

The south-east region of Algeria suffers from a great socio-economic problem that affects a large population. Faced with the unavailability of drinking water, solar distillation; which appears to be a suitable and inexpensive solution; was adopted by local researchers. Improving the productivity of a solar greenhouse distiller is the subject of several researches in the world. As it is well known, distiller with simple glazing is wildly studied but unfortunately has feeble efficiency. Double glazing is a method that increases the efficiency of a flat solar collector. The idea is to use the same technique on a single-slope solar distiller (50 x 50 cm). Two glass plates separated by 1 cm between them air is trapped. Experience shows that this technique has a negative effect on the productivity of the distiller with a rate of 88.63%; it means 9 times. So double glazing is not recommended in the single slope solar distiller. Résumé Le sud-est de L’Algérie souffre d’un grand problème socio-économique qui touche une large population. Face à l’indisponibilité de l’eau potable, les chercheurs locaux adoptent la distillation solaire qui apparaît comme une solution convenable et non coûteuse. L’amélioration de la productivité d’un distillateur solaire à effet de serre et l’objet de plusieurs recherches dans le monde. Le double vitrage est une méthode qui augmente le rendement d’un capteur solaire plan. L’idée est d’utiliser la même technique sur un distillateur solaire à simple pente de (50 x 50 cm) et de le couvrir avec deux plaques de verre séparées de 1 cm, c'est-à-dire que l’air est emprisonné entre les deux verres. L’expérience montre que cette technique à un effet négatif sur la productivité du distillateur qui se voit diminuer jusqu’à 9 fois par rapport au distillateur avec un simple vitrage. Donc le double vitrage est déconseillé dans le distillateur solaire à simple pente.

Methylamine lead tri-iodide (MAPbI3 or CH3NH3PbI3) is a promising organic/inorganic perovskite material in photovoltaic applications. It attracted researcher's attention for its good power conversion efficiency that stepped from 3.8 % in 2009 to up to 22 % in 2018. In this paper is reported a new low-cost method to fabricate CH3NH3PbI3 which is the spray pyrolysis with moving nozzle. Then it is reported different optical and electrical characteristics of the resulting perovskite. Results promote that a molarity of 2 moles and a processing temperature of 100°C can improve optical properties.