This work presents a theoretical and experimental study of a double slope still with fins immersed in a basin. The influence of the speed of wind, distance between fins, height of fins, number of fins and thickness of the water layer in the basin, on the production of the still, is investigated. From the results obtained, it is noted that for a wind speed greater than 3.5 m/s, a decrease in the productivity is caused by the cooling of the outer walls, and this induces some heat losses, especially at the front and rear walls of the still. The distance between fins has no significant effect on the still productivity. Moreover, increasing the height of fins, from 2 to 5 cm, causes a raise in the productivity; however, when the height changes from 6 to 8 cm, the distillate production goes down. A larger number of fins lead to a rise in the amount of distilled water produced. Therefore, one should use the maximum number of fins, while taking into consideration the feasibility of the assembly. Increasing the mass of water in the basin makes the productivity to go down. The results obtained on June 11, 2016, show that the productivity of the proposed system was about 15 to 27 % higher than that of a simple one, under the following conditions, i.e. mw = 42.61 kg, h1 = 3.6 cm, Vv = 3.5 m/s, lw = 5 cm and Nfins = 12.

The equilibrium water content of a product to be dried is essential during a forced convection solar drying and storage operation. These values are often taken from the so-called isothermal sorption curves. The isotherms determination is an essential step to know the distribution and the intensity of the water connections in the products. They make it possible to determine the products final water content to be reached in order to optimize the drying conditions and give valuable information on the hygroscopic equilibrium. As a result, this experimental study aims to determine the physicochemical components' and the desorption isotherms curves for deferent date type L'hmira, Bamakhlouf and Tegazza from the Touat region, in SouthWest Algeria, using the saturated salt solution method. The experiment is carried out for three temperature values 40 ° C, 50 ° C and 60 ° C, to study the influence of the temperature on the equilibrium curves of the product and finally to describe the isothermal moisture desorption for deferent date types for three temperatures using known models of GAB, SMITH, LANGMUIR and OSWIN.

The Purpose of the paper is studied three types solar distillers, double slope with and without immersed fins and the simple solar distiller. A monthly comparative study is investigated experimentally, for a long period of the year. Further, the wind speed influence, the distance between fins, the fins height, the fins number and thickness, on the solar distiller's production, is investigated theoretically. From the obtained results, it is noted that for the wind speed greater than 3.5 m/s, a decrease in the productivity is caused by the cooling of the outer walls, and this induces some heat losses, especially at the front and rear walls of the solar still. The distance between fins has no significant effect on the still productivity. Moreover, increasing the fins height, from 2 to 5 cm, increase the productivity; however, when the height changes from 6 to 8 cm, the distillate production goes down. A larger fins number lead for rise the produced distilled water amount. Therefore, one should use the maximum number of fins, while taking into consideration the feasibility of the assembly. Increasing the water mass makes the productivity to go down. The obtained results on June 11, 2016, show that the proposed system productivity was about 15 to 27 % higher than that of a simple one, under the following conditions, i.e. Mw = 42.61 kg, h1 = 3.6 cm, Vw = 3.5 m/s, lw = 5 cm and Nfins = 12. The total annual cost estimation proof clearly that the payback period is less than a years. As well as, it has been found that the increasing lifetime and the interest rate decreasing caused a decrease in the distilled water unit price.

This work presents a theoretical and experimental study of a double slope still with and without immersed fins compared to the single solar still monthly production. The influences of the distance between fins, fin heights, fin numbers and water layer thickness on the solar still production have been widely researched. From the obtained results, the distance between fins has no significant effect on the still productivity. Moreover, for fin heights from 2 to 5 cm, cause the productivity raising, when the fin heights are from 6 to 8 cm found an increasing in the still production. A larger fin numbers lead to a rising in the produced water amount. The water quantity augmentation in the basin makes the water productivity decreasing. The experimentally obtained results during the day June 11, 2016, show that the solar still with immersed fins productivity was about 15 to 27 % higher than that of the simple solar still, under the following conditions, i.e. mw = 42.61 kg, h1 = 3.6 cm, Vw = 3.5 m/s, lw = 5 cm and Nfins = 12.

The fresh tomato is a very perishable product in arid regions for that the drying is an indsipendable technique to preserve this product and used at all times, in this study the fresh tomatoe was sampled from different farms in Adrar and subjected to the drying method using an indirect dryer solar. The dried tomatoes were screened for microbiological and physicochemical analysis including E. coli, Staphylococcus aureus, Salmonella Typhi, anaerobic sulfito- redactors, molds and yeasts in addition, the value of pH, water activity, dry matter, and assay of ash. The obtained results showed the presence of mesophilic aerobic total bacteria, and coliform total, the absence of Salmonella Typhi, Staphylococcus aureus, Clostridium perfringens and spores of anaerobic sulfito reducting and some colonies of yeasts, for the pH value, activity water, dray matter and assay of ash, the results were (4.10), (0.41), (9.63%) and (5.71%) respectively, which do not affect the final quality of the dried products and satisfactory to norms imposed by the commercial legislation of Algerian. On the other hand, the isothermal sorption is indispensable step to mastering the process of drying tomatoes, and to know the distribution and the intensity of the water connections in the products as a result, this experimental study aims to determine the physicochemical components' and the desorption isotherms curves for tomato harvested from the Touat region, in South-West Algeria, using the saturated salt solution method. The experiment is carried out for three temperature values 40℃, 50℃ and 60℃, to study the influence of the temperature on the equilibrium curves of the product and finally to describe the isothermal moisture desorption for tomato product for three temperatures using known models of GAB, GAB, modified BET who showing the best models isotherms sorption to model at and predict hygroscopic behavior during drying and storage. The results of this research can be used to determine characteristic drying curves and to have optimal storage conditions.

The purpose of the present work is to carry out an overheating study of planar solid oxide fuel cells at supported anode that operate at an intermediate temperature (AS-IT-SOFC) according to a three-dimensional and stationary numerical model. In this work, the heat is supposed produced according to four processes of heat generation (the Ohmic source that is due to the Joule effect, the source due to the species concentrations, the activation source that is caused by activation of different chemical reactions produced in the two electrodes, the electrochemical source due to the water formation in the anode). The results are obtained from a FORTRAN language program realized locally, which is based on the finite difference method in a three-dimensional environment. From the obtained results analysis, it became apparent that the developed model for the AS-IT-SOFC overheating study allowed us to understand the impact of each heat source on the temperature elevations and distributions in AS-IT-SOFC. The greatest heat production is that generated by the Ohmic source, it is about 80.6% for gas inlet temperatures of 883 K. The smallest heat production is that obtained by the source of concentration that is negligible compared to other sources. The heat produced by the electrochemical source is greater than that generated by the activation source, their heat productions are almost 17 and 2.3% for gas inlet temperatures of 883 K respectively.

During a forced convection sun drying and storage operation, the equilibrium water content of a product to be dried is critical. These figures are frequently derived using isothermal sorption curves. The calculation of isotherms is a necessary step in determining the distribution and intensity of water connections in products. for that this paper concentrates on the experimental determination of the adsorption-desorption isotherms for various temperatures (40, 50, and 60℃) of the Nicotiana Tabacum L plants. From which we had established the relationship between the water activity and the water content in the product. However, the aforementioned determination was carried out by the static gravimetric method. Eight saturated salt solutions have been utilized in applications such as (KOH, KCl, MgCl2, MgNO3, K2CO3, BaCl2, K2SO4, and NaCl). Hygroscopic equilibrium was completed after 13 days for temperature 40℃, 11 days for 50℃, and 9 days for 60℃. The overall experimental sorption curves are summarized by six models (HENDERSON, modified HALSEY, OSWIN, GAB, modified BET, and PELEG). The sorption isotherms built using the Clausius–Clapeyron equation were used to determine the net isosteric temperatures of desorption and adsorption of Nicotiana Tabacum L. The results for the adsorption-desorption isotherms found are type III according to IUAPC. Following the smoothing of the experimental results by different used models, it was found that the models of GAB and Peleg allow having the lowest mean relative errors and correlation coefficient.

In this work, a steady-state three-dimensional model is employed to investigate the heat transfer phenomena in a Planar Solid Oxide Fuel Cell (P-SOFC) and determine the current density impact on the overheating of this fuel cell type. The thermoelectric characteristics of various components of the P-SOFC are provided from the standard materials: Ni-YSZ for the anode, YSZ for the electrolyte, La1-xSrxMnO3 for the cathode, and LaCrO3 for the interconnectors. The partial differential equations governing the heat transfer phenomena in the different cell parts are modelled using the finite difference method in a threedimensional environment. A program in FORTRAN language is locally developed for solving simultaneously the discretized heat conduction equation. The interest of this work is focused on determining the temperature profiles, fields, and distributions as well as evaluating and analysing the heat created by the current densities produced by the cell itself. The obtained results' analysis shows that for the considered geometric configuration, the P-SOFC components' heating is found to be proportional to the electric energy production.