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The study concerns an autonomous individual solar water heater installed in the Oran region in Algeria. Supplied by two sources of solar thermal and photovoltaic energy, this solar water heater provides domestic hot water for the needs of an average family of 6 people. A comparative approach was made to find the most adequate solution between increasing the surface area of the thermal solar panel or those of the photovoltaic panels, by analyzing the solar fraction and the efficiency of the thermal panels. The choice was make for a thermal panel with a surface area of 4 m2 and complete with 16 photovoltaic panels, thus resulting in a total surface area of 14 m2 to obtain an autonomous solar water heater powered only by solar energy. Another option was considered by incorporating a photovoltaic thermal panel, and substantial savings were found.

In the desalination field, the membrane distillation (MD) is a new process of producing distilled water that has been developed and tested in recent years. In this paper, the integrated single cassette air-gap membrane distillation (AGMD) module in the solar thermal desalination system is validated and numerically simulated with the TRNSYS program. This model is studied to be ideal for obtaining a distilled water flow rate of 5.5 kg/h at different times under changing climatic conditions throughout the year in Ain-Temouchent weather, Algeria. The auxiliary heater is added to ensure the thermal energy continuity in the cold climatic conditions, where the photovoltaic system is used to power electrically the auxiliary heater. Therefore, the energy needed is calculated for the auxiliary heater and is replaced by 10 photovoltaic panels, each one has an area of 1.6 m² using seven of the energy storage batteries (12V, 200Ah) with 1.5 KW via TRNSYS and PVGIS help programs. Simulated results showed excellent compatibility with experimental results in previous studies. Additionally, it was found that when the inlet temperature of AGMD reaches 85 °C, the distilled water flow from the distillation membrane reaches 5.5 kg /h and that remains stable on different days throughout the year by relying solely on solar energy.

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A critical problem in the application of metal matrix composites is the presence of high residual thermal stresses induced during the development process. These thermally induced stresses are generally detrimental to the service life of this type of composite. This article discusses the influence of maximum residual stresses on the intensity factor. The results interpreted in terms of damage, allowed us to identify the risk zones; characterized by a significant level of maximum residual stresses (S11Max, S22Max, S33Max), namely the particle/Matrix interface. The results also show that the loading conditions and the inter-distance between matrix and particle with two interfacial cracks have an important effect on max residual stresses and stress intensity factors.