Heat transfer process and fluid flow in a solar chimney used for natural ventilation are investigated numerically and experimentally her in. Solar chimney was designed, manufactured and tested by selecting different positions of air entrance namely: bottom entrance, side entrance, and both side and bottom entrances. The effect of integrating the chimney with paraffin (phase change material) on its thermal behavior has been also investigated. CFD analysis based on finite volume method is used to predict the thermal performance, and fluid flow in two-dimensional solar chimney under unsteady state condition, to identify the effect of different parameters such as solar radiation, and inclination angle. Experimental results show that a solar chimney with side entrance gives better thermal performance; also integrating solar chimney with PCM extended the ventilation period after the sunset. A comparison between the numerical and the experimental results shows fair agreement.
This study reports on natural convection heat transfer in a square enclosure of length (L=20 cm) with a saturated porous medium (solid glass beads) having same fluid (air) at lower horizontal layer and free air fill in the rest of the cavity's space. The experimental work has been performed under the effects of heating from bottom by constant heat flux q=150,300,450,600 W/m2 for four porous layers thickness Hp (2.5,5,7.5,1) cm and three heaters length δ(20,14,7) cm. The top enclosure wall was good insulated and the two side walls were symmetrically cooled at constant temperature. Four layers of porous media with small porosity, Rayleigh number range (60.354 - 241.41) and (Da) 3.025x10-8 has been investigated. The obtained data of temperatu
... Show MoreAsmari is the main productive reservoir in Abu Ghirab oilfield in the south-east part of Iraq. It has history production extends from 1976 up to now with several close periods. Recently, the reservoir suffers some problems in production, which are abstracted as water production rising with oil production declining in most wells. The water problem type of the field and wells is identified by using Chan's diagnostic plots (water oil ratio (WOR) and derivative water oil ratio (WOR') against time). The analytical results show that water problem is caused by the channeling due to high permeability zones, high water saturation zones, and faults or fracturing. The numerical approach is also used to study the water movement inside the reser
... Show MoreAsmari is the main productive reservoir in Abu Ghirab oilfield in the south-east part of Iraq. It has history production extends from 1976 up to now with several close periods. Recently, the reservoir suffers some problems in production, which are abstracted as water production rising with oil production declining in most wells. The water problem type of the field and wells is identified by using Chan's diagnostic plots (water oil ratio (WOR) and derivative water oil ratio (WOR') against time). The analytical results show that water problem is caused by the channeling due to high permeability zones, high water saturation zones, and faults or fracturing. The numerical approach is also used to study the water movement insi
... Show MoreIn this paper the specific activity of 238U, 232Th and 40K
radionuclides were determined by sodium iodide enhanced by
thallium NaI(Tl) detector and assessment the annual effective dose
in samples of powder milk from different companies such as
Almunaish, Seven Caw, Molty and Altunsa for adult available in
Baghdad markets. The specific activity of 40K has the greater value in
all the samples which is in the range of allowed levels globally that
suggested by UNSCEAR. The mean value of annual effective doses
were 0.121, 0.314775 and 0.305 mSv/y for 238U, 232Th and 40K
respectively.
This paper presents an experimental study of cooling photovoltaic (PV) panels using evaporative cooling. Underground (geothermal energy) water used to extract heat from it during cooling and cleaning of PV panels. An experimental test rig was constructed and tested under hot and dusty climate conditions in Baghdad. An active cooling system was used with auxiliary an underground water tank to provide cold water as a coolant over both PV surfaces to reduce its temperature. The cellulose pad has been arranged on the back surface and sprays cooling on the front side. Two identical PV panels modules used: without cooling and evaporative water cooling. The experiments are comprised of four cases: Case (I): backside cooling, Ca
... Show MoreA new way to Systems concentrates have been clarified and that allows a concentration high and analysis to automatically wavelengths of the spectrum of this system analyst of the spectrum and the center is built on Holucram Nafez gives less absorbency with efficient diffraction high when the wavelength (900 nm), which will be useful for Khallaya solar
Alginate is one of the natural biopolymers that is widely used for drug formulations, combination of alginate with other polymers, such as gum acacia, pectin, and carrageenan can increase mechanical strength, therefore, can reduce leakage of the encapsulated active pharmaceutical ingredient from the polymer matrix. Interaction of alginate and these polymers can occur via intermolecular hydrogen bonds causing synergism, which is determined from the viscosity of polymer mixture.
Alginate was combined with gum acacia/pectin/carrageenan in different blending ratios (100:0, 75:25, 50:50, 25:75, and 0:100) with and without addition of CaCl2. The synergism effect is obtained from the design of experimental (DoE), and calculati
... Show MoreProject deal with the study of the suitability of the planning standards of the select sites for sports facilities for the holy city of Karbala and the extent of convergence and divergence between these standards and points of strength and weakness in each of these standards.
It was found that there was a lack of the role given to the sports as a kind of luxury does not deserve to spend money and efforts, and was then incorporated with a lot of entertainment services by planners.
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... Show MoreThe current research deals with practical studies that explain to the Iraqi consumer multiple instances about the phenomenon of water hammer which occur in the water pipeline operating with pressure. It concern a practical study of the characteristics of this phenomenon and economically harmful to the consumer the same time. Multiple pipe fittings are used aimed to reduce this phenomenon and its work as alternatives to the manufactured arresters that used to avoid water hammer in the sanitary installations, while the consumer did not have any knowledge as to the non-traded for many reasons, including the water pressure decreases in the networks and the use of consumer pumps to draw water directly from the network. Study found a numbe
... Show MoreThe current research deals with practical studies that explain to the Iraqi consumer multiple instances about the phenomenon of water hammer which occur in the water pipeline operating with pressure. It concern a practical study of the characteristics of this phenomenon and economically harmful to the consumer the same time. Multiple pipe fittings are used aimed to reduce this phenomenon and its work as alternatives to the manufactured arresters that used to avoid water hammer in the sanitary installations, while the consumer did not have any knowledge as to the non-traded for many reasons, including the water pressure decreases in the networks and the use of consumer pumps to draw water directly from the network. Study found a number of
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