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Experimental Evaluation of PV Panel Efficiency Using Evaporative Cooling Integrated with Water Spraying
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In this work, an inventive photovoltaic evaporative cooling (PV/EC) hybrid system was constructed and experimentally investigated. The PV/EC hybrid system has the prosperous advantage of producing electrical energy and cooling the PV panel besides providing cooled-humid air. Two cooling techniques were utilized: backside evaporative cooling (case #1) and combined backside evaporative cooling with a front-side water spray technique (case #2). The water spraying on the front side of the PV panel is intermittent to minimize water and power consumption depending on the PV panel temperature. In addition, two pad thicknesses of 5 cm and 10 cm were investigated at three different water flow rates of 1, 2, and 3 lpm. In Case #1, the evaporative cooling decreased the temperature of the PV panel by about 15 ℃ related to the uncooled PV panel for both pad thicknesses. While case #2 showed a more significant temperature drop for PV panel by about 27 ℃  and 29.7 ℃ for pad thicknesses of 5 cm and 10 cm, respectively. Compared to the uncooled PV panel, the cooled panel had a distinct enhancement in performance. The efficiency of the PV panel in case #1 was augmented by 5.7% with 50 mm pad thickness and 8.4% for 100 mm pad thickness. Case #2 revealed more improvement in the efficiency by 9% for 5 cm and up to 20% for 10 cm pad thickness. The PV panel electric power was augmented by 7.3% and 13.8% for 2 and 3 lpm water flow rates, respectively. Compared to the flow rate of 1 lpm. The open voltage circuit improved by 4.1% and 9.4% for cases #1 and #2, respectively. The higher air temperature drop was about 11.4 ℃ for case #2 at 10 cm pad thickness.

 

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Publication Date
Wed Aug 01 2018
Journal Name
International Journal Of Novel Research In Electrical And Mechanical Engineering
Use of Panel Method in High Subsonic and Transonic Aerodynamic Analysis of Complex Aircraft Configuration
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The application of low order panel method with the Dirichlet boundary condition on complex aircraft configuration have been studied in high subsonic and transonic speeds. Low order panel method has been used to solve the case of the steady, inviscid and compressible flow on a forward swept wing – canard configuration with cylindrical fuselage and a vertical stabilizer with symmetrical cross section. The aerodynamic coefficients for the forward swept wing aircraft were calculated using measured wake shape from an experimental work on same model configuration. The study showed that the application of low order panel method can be used with acceptable results

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Publication Date
Sun Mar 01 2020
Journal Name
Iraqi Journal Of Physics
Increasing the conversion efficiency of KTP crystal using the pump-power technique
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In this study, the effect of pumping power on the conversion efficiency of nonlinear crystal (KTP) was investigated using laser pump-power technique. The results showed that the higher the pumping power values, the greater the conversion efficiency (η) and, as the crystal thickness increases within limitations, the energy conversion efficiency increases at delay time of (0.333 ns) and at room temperature. Efficiency of 80% at length of KTP crystal (L = 1.75 X 10-3 m) and Pin = 28MW, and also, compare the experimental results with numerical results by using MATLAB program. 

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Publication Date
Sat Jul 28 2018
Journal Name
Journal Of Engineering
Experimental and Numerical Analysis of Expanded Pipe using Rigid Conical Shape
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The experimental and numerical analysis was performed on pipes suffering large plastic deformation through expanding them using rigid conical shaped mandrels, with three different cone angles (15◦, 25◦, 35◦) and diameters (15, 17, 20) mm. The experimental test for the strain results investigated the expanded areas. A numerical solution of the pipes expansion process was also investigated using the commercial finite element software ANSYS. The strains were measured for each case experimentally by stamping the mesh on the pipe after expanding, then compared with Ansys results. No cracks were generated during the process with the selected angles. It can be concluded that the strain decreased with greater angles of con

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Publication Date
Sun Apr 07 2013
Journal Name
Journal Of Educational And Psychological Researches
Determinants of using experimental groups and choosing reasons in psychological researches
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Until The Second Half Of Nineteenth Century  , Psychology Depended On Philosophy In Its Experiences Which Means It Depend On Individuals Feelings Toward Psychological Experiences And Rapid Observation . As For The Scientific Organized Experimentation And Observation By Machines Have Been Used Later   .

The Experimentation Looking For The Cause Of  Phenomena And How Is That Happened   Also Reveal The Causal Relationship Between Among Phenomena . The Experiences In Psychology Field Include In Its Simplest Form Only One Variable ( Effective) Which Is Called Independent Variable As Well As Another Variable ( Affected )   That Called  Dependent Variable .

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Publication Date
Fri Jul 01 2022
Journal Name
Iraqi Journal Of Science
The Effect of Expected Water Shortage on Net Primary Productivity and Rain Use Efficiency in the Tigris-Euphrates Basin
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Tigris and Euphrates Rivers, originating in Turkey and cutting through both Syria and Iraq, have experienced drastic reductions in water flows in recent years due to increasing water demand, hydro-engineering projects, and climate change. The decline in water flows has led to decreased agricultural yields. Iraq reported its worst cereal harvest in a decade in 2009, indicating that with a decline in water supplies, a potential food security problem emerges. This study, therefore, addressed the effect of water availability on (1) Net Primary Productivity (NPP) and (2) Rain Use Efficiency (RUE) in the Tigris-Euphrates (T-E) basin. Results displayed that NPP increases significantly from the arid and semi-arid sites in the south to the wetter

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Publication Date
Fri May 01 2020
Journal Name
Journal Of Engineering
Thermal Efficiency for Passive Solar Chimney with and Without Heat Storage material
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In this study, a different design of passive air Solar Chimney(SC)was tested by installing it in the south wall of insulated test room in Baghdad city. The SC was designed from vertical and inclined parts connected serially together, the vertical SC (first part) has a single pass and Thermal Energy Storage Box Collector (TESB (refined paraffin wax as Phase Change Material(PCM)-Copper Foam Matrix(CFM))), while the inclined SC was designed in single pass, double passes and double pass with TESB (semi refined paraffin wax with copper foam matrix) with selective working angle ((30o, 45o and 60o). A computational model was employed and solved by Finite Volume Method (FVM) to simulate the air i

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Publication Date
Tue Aug 01 2017
Journal Name
International Journal Of Scientific & Engineering Research
Integrated System of Information hiding by Applying Three levels
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MB Mahmood, BN Dhannoon

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Publication Date
Sat Sep 01 2007
Journal Name
Al-khwarizmi Engineering Journal
Parametric study of thermal behavior of thrust chamber cooling channels
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A numerical investigation is adopted for two dimensional thermal analysis of rocket thrust chamber wall (RL10), employing finite difference model with iterative scheme (implemented under relaxation factor of 0.9 for convergence) to compute temperature distribution within thrust chamber  wall (which is composed of Nickel and Copper layers). The analysis is conducted for different boundary conditions: only convection boundary conditions then combined radiation, convection boundary conditions also for  different aspect ratio (AR) of cooling channel. The results show that Utilizing cooling channels of high aspect ratio leads to decrease in temperature variation across thrust chamber wall, while no effects on heat transferred to the

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Publication Date
Wed Oct 14 2020
Journal Name
Plant Archives
EVALUATION OF THE EFFICIENCY OF SOME CHEMICAL (FYLEX), NANOPARTICLES (MGO) AND BIOLOGICAL FACTORS IN INHIBITING OF ASPERGILLUS FLAVUS
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The Fylex extract exert a high inhibition effect against A . flavus growth on PDA medium, as the fungus growth was completely inhibited by 100% at a concentration of 0.2 and 0.3% of studied extract, while the lowest inhibition percentage (71%) was found at a concentration of 0.1%. Whereas magnesium oxide nanoparticles showed the highest inhibition ratio of A. flavus (100%) was detected at 0.2% and the lowest inhibition ratio (81.66%) was at concentration 0.5%. Moreover, the addition of G. lucidum powder to PDA medium with a concentration of 2.5 mg increased the inhibition rate of A. flavus growth which was 54.4%, while the lowest inhibition ration (18.22%) was found at a concentration of 1000 mg. The milky liquid (brocade milk) of Calotropi

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Publication Date
Fri Sep 14 2018
Journal Name
Radiation Effects & Defects In Solids
Effect of gamma and beta radiation on I–V characterization of the solar cell panel
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Optoelectronic devices, widely used in high energy and nuclear physics applications, suffer severe radiation damage that leads to degradations in its efficiency. In this paper, the influence of gamma radiation (137Ce source) and beta radiation (90Sr source) on the photoelectric parameters of the Si solar cell, based on the I–V characterization at different irradiation exposer, has been studied. The penetrating radiation produces defects in the base material, may be activated during its lifetime, becoming traps for electron–hole pairs produced optically and, this will, decrease the efficiency of the solar cell. The main objective of the paper is to study and measure changes in the I–V characteristics of solar cells, such as efficienc

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