In 1984 (Attaseth) and his group manufactured two similar vertical distillers for the purpose of studying the effect of different glass and plastic covers on the rate of productivity, and they noticed that the productivity of the distilled glass cover is higher than in the case of plastic covers up to 10%. [2]
In 1994 at Brunel University in the city of Oxford in Britain, researchers presented (Mahdi and Smith) a design for a solar filament destiller using concentrated solar reflectors. The study was carried out in summer and winter and to show the effect of the reflector. The researchers concluded that the distillate's productivity in the summer without the reflector is greater than the productivity of thedestiller with reflector and the reverse state in the winter season as the productivity increases with the presence of the reflector more than in the absence of it. [3]
In the year 2000 (Tanaka), an applied study was carried out to design a set of rectangular cells with an inter-dimensional dimension between two 5mm plates. It also contains a piece
7 | P a g e of tissue attached to the hot plate of the cell. The solar distillator used is a single slope type.
Theoretical results have concluded that if the number of cells increase the productivity . Theoretically, the proposed output reaches more than 15 kg/m2/d for 10 cells with an intermediate dimension of 5mm, for solar radiation of 22.4MJ / m2 / d. [4]
As a result of the increase in the rate of vapor trapped inside the solar distiller, which creates additional pressure,( El-Bahi) thought, to reduce the effect of this phenomenon by opening a small incision to pass the vapor to a second condensing room, reinforced with an additional condenser and a reflector of radiation, which gives him an advantage to improve the performance of the device. The daily production rate of this design is about 7 L/m2 /d, where its efficiency decrease to 70% when it works by adding the condenser, but it increases to 75% as soon as we abandon the condenser. [4]
Chaibi (2000) completed a numerical study on a greenhouse prepared for cultivation and containing a solar distiller directed towards the direction of solar radiation
This distiller consists of transparent materials for incident radiation. Through the authorized results, this proposed model is suitable for use in areas with a dry climate in order to adapt climatic conditions to help plants grow in areas that lack moisture, and distilled water can be produced for use in the watering process. The productive capacity obtained from this model is estimated about 1-1.6 kg/m/J, and therefore this model is among the proposed systems for the production of fresh water for use in irrigation of agricultural crops. [4]
Boukar and Harmim (2001) have experimentally demonstrated the efficacy of vertical solar distillers when using the evaporative water flow feature on a sponge cloth surface. The same research indicated that the rate of production doubles automatically with the increase in the temperature of the desert region and the increase in the temperature of the glass cover, as the study showed over a period of 4 months that the productivity of such a vertical distillate varies from 0.5 to22.3 kg / m2. [4]
In 2006 in the Indian city of New Delhi, the researcher (Tiwari) studied the effect of water depth on the productivity of the solar distillate in the summer. Where he took the clear cover angle 30 ° and readings were taken for 24 hours for five different days and for five different depths of water in the distilled basin starting with a depth of 0.4 meters and ending with a depth of 0.18 meters. It was found that the productivity of the solar distillery decreases with increasing depth of water in the basin. [3]
8 | P a g e In 2007 at Al-Balqa Applied University in Amman, the researcher, Badran, conducted an experimental study to improve the production of single slope distiller. Where the study was carried out on various factors such as painting the asphalt basin or spraying it and changing the depth of the water. This study found that productivity increases by 51% when asphalt coating and productivity increases by reducing the depth of the water in the distiller. Badran showed the effect of external conditions. At night, productivity is about 16% of daily production with solar radiation due to the difference between the heat bike for water and the outer cover. [3]
Bechki (2010) piloted a simple double-slope solar distiller in southern Algeria on the basis of partial shading of intermittent periods of one side of the glass cover in order to reduce its temperature and improve condensation performance. This work gave an improvement of 12% of daily output [4]
In 2011, the two researchers (Walke and Teltumbade) in the Indian city of Maharashtra presented an experimental study on single-slope solar distillers using various radiation absorbent materials in the inner basin where they used a rubber mat as well as black ink and sponge. It turned out that the rubber is more effective, followed by black ink, which was finally made of sponge. As we have shown through their studies, the internal heat is chosen over production, and they found that with increasing internal heat, production increases [3].
The main objective of his work (2011 Zeroual) was to enhance the daily yield of the simple double slope solar distiller by improving the performance of the condenser. This was accomplished by cooling one of its condensed surfaces. As a result, two series of experiments were carried out. In the first group, the northern cover was cooled with flowing water on its entire outer surface, so productivity increased by 11.8%. As for the second series, the northern glass temperature was lowered by setting intermittent shadows at intervals of (12:00 to 14:00), the improvement rate for this procedure was about 2.94%. (4)
I-4 Principle of solar distiller:
The principle of the solar distiller is the same as the principle of the natural phenomenon of solar distillation. When the solar radiation falls on the water (oceans, lakes and rivers), this water is heated and then evaporates and rises to the top. The vapor travels through the wind until it reaches a cooler place, joining together and clouds forming as rain or snow. The
9 | P a g e principle of the solar distiller is as follows: the water in the basin is heated by sunlight and evaporates, the resulting water vapor is transferred on the inner side of the cover at a temperature between the salt water temperature at the base and the surrounding temperature.
The water droplets formed flow over the inner glass cover by its weight to the distilled water collection bowl (Figure I-1). [5]