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Numerical Investigation of Aerodynamic Characteristics of Supercritical RAE2822 Airfoil with Gurney Flap
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Gurney flap (GF) is well-known as one of the most attractive plain flaps because of the simple configuration and effectiveness in improving the lift of the airfoil. Many studies were conducted, but the effects of GF on the various airfoil types need to be further investigated. This study aimed to clarify the effect of GF in the case of the supercritical airfoil RAE2822. This research includes a steady, two-dimensional computational investigation carried out on the supercritical airfoil type RAE-2822 to analyze Gurney flap (GF) effects on the aerodynamic characteristics of this type of airfoil utilizing the Spalart-Allmaras turbulence model within the commercial software Fluent. The airfoil with the Gurney flap was analyzed for three different height values 1%c, 2%c, and 3%c, and five mounting angles (30°,45°,60°,75°, and 90°) with the axial chord for angles of attack (-1°,-2°,-3°,0°,1°,2°,3°). The calculations showed that when GF height is increased, the maximum suction pressure on the upper surface increases by 25.4%, 36.5%, and 68.83% when the height of the Gurney flap is 1%c, 2%c, and 3%c, respectively, compared with that on the airfoil without GF. The lift coefficient was also increased, and the shock waves moved downward by increasing GF height. As Gurney flap heights increase, the drag coefficient increases gradually for positive angles of attack but for negative angles of attack. The drag coefficient also decreases with increasing the GF heights. As long as the angle of the mounting is between 45o and 90o, the lift coefficient does not differ on a large scale. For mounting angles less than 45o, the lift coefficient drops quite fast. As a result, reducing the Gurney flap’s lift enhancement and the drag coefficient increases gradually for positive angles of attack, but for negative angles, it can be noted that the drag coefficient decreases with increasing the mounting angles of GF. The calculated values of the lift and drag coefficients with an attack angle and pressure coefficient compared with the experimental values, and a good agreement was noticed. 

 

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Study of alumina prepared from Iraqi kaolin
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The current research was conducted to report the synthesis of alumina powder from Iraqi kaolin. The kaolin was transformed to metakaolin by calcinations at temperature 800 °C for three hours. Then the calcined kaolin was treated with (1.5 M) from H2SO4 for 6 hours to form Al2(SO4)3.12H2O solution. The precipitate was dried at 80oC for 10 hours and calcinations at different temperatures for two hours. The samples which result was characterized by X–Ray diffraction (XRD) and X–Ray fluorescence (XRF). The results indicate to the crystalline hydrate aluminum sulfate for the sample that be as – synthesis and when calcinations at 600 oC transformed into aluminum sulfate phase. The phases of alumina which we obtain consisted of a gamma a

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Publication Date
Mon Jan 08 2024
Journal Name
Al-academy
Aesthetics of experimentation In short television films
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Experimentation Multi effective and fertile grew human desire to discover new ways to express beauty in artwork .And dabble term experimentation in the performing arts and arts architecture, cinema and television in the test forms and interest in the visual effects and movements seek to establish and beauty and schools of thought in literature and art. This study aims to identify

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Publication Date
Sun Dec 30 2012
Journal Name
Al-kindy College Medical Journal
Evaluation of Medication Errors in Hospitalized Patients
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Objectives: Many medication errors occur in the hospital, and these can endanger patients. The purpose of this study was to evaluate the incidence of medication errors in hospitalized patients, and to categorize the most frequent types of errors, and to asses the possible measures that may prevent the occurrence of such errors.
Methods: A prospective, exploratory, and evaluative study, using direct observation method to detect medication errors in adult hospitalized patients in medical and surgical units in Baquba Teaching Hospital- Diyala-Iraq.. The files of 299 patients had been reviewed from July 2009 to September 2009, including medication orders and treatment sheets to detect existing errors. The detected errors were recorded and

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Publication Date
Fri Jun 01 2018
Journal Name
Journal Of The College Of Languages (jcl)
A Pragmatic Study of English Honorific Forms
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         It is axiomatic that languages mirror  the world view of their users. Manipulating honorific forms  among people inevitably reflects this truth . Honorifics are conventionalized forms or expressions  manifested in all the world's languages and  are used to  express the social status of the participants in the verbal interaction and to convey indications like politeness and respect  . English is no exception. However the question is what exactly creates these forms and their meanings. Although  honorifics have been extensively researched from a grammatical and semantic  angle  , yet they haven’t received that significant  attention  i

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Engineering
Improvement of Gypseous Soil Using Cutback Asphalt
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Gypseous soils are widely distributed and especially in Iraq where arid area of hot climatic is present. These soils are considered as problematic soils; therefore this work attends to improve the geotechnical properties of such soil and reduce the dangers of collapse due to wetting process. In this research, undisturbed soil sample of 30 % gypsum content from Karbala city is used. The Single Oedometer collapse test is used in order to investigate the collapse characteristics of natural soil and after treatment with 3%, 6%, 9%, 12% and 15% of Cutback Asphalt. Moreover, two selected additive percentages (9% and 12%) are used to evaluate the suitability of using the Cutback Asphalt for improvement of the bearing capacity o

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Engineering
Mismanagement Reasons of the Projects Execution Phase
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The execution phase  of the project is most dangerous and the most drain on the resources during project life cycle, therefore, its need to monitor and control by specialists to exceeded obstructions and achieve the project goals. The study aims to detect the actual reasons behind mismanagement of the execution phase. The study begins with theoretical part, where it deals with the concepts of project, project selection, project management, and project processes. Field part consists of three techniques: 1- brainstorming, 2- open interviews with experts and 3- designed questionnaire (with 49 reason. These reasons result from brainstorming and interviewing with experts.), in order to find the real reasons behind misman

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Publication Date
Mon Mar 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Nonlinear Adaptive Control of a pH Process
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In this paper a nonlinear adaptive control method is presented for a pH process, which is difficult to control due to the nonlinear and uncertainties. A theoretical and experimental investigation was conducted of the dynamic behavior of neutralization process in a continuous stirred tank reactor (CSTR). The process control was implemented using different control strategies, velocity form of PI control and nonlinear adaptive control. Through simulation studies it has been shown that the estimated parameters are in good agreement with the actual values and that the proposed adaptive controller has excellent tracking and regulation performance.

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Publication Date
Wed Oct 05 2016
Journal Name
Al-academy
The concept of rhythm in the play
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The training of great importance in the play, in building optic and intellectual broadcast codes tags, and then comes after the recipient at the reception of such codes and decoded tags, and is the rhythm, the color of the most important elements of configuration, consistent with other elements, Kaltmathl, and focus, and harmony, and dissonance

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of The College Of Education For Women
Conservation of Concept among Children: Semantic Study
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Conservation of Concept among Children: Semantic Study

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Publication Date
Fri Jan 05 2024
Journal Name
Al-academy
Mechanisms of visual attraction in interior spaces
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The visual attraction of the fundamentals that require the availability in the design business, to achieve the needs of different social interactive and the need for recreation or entertainment as well as financial need and as such has considered the importance of a researcher studying the mechanics of visual attractions in the interior spaces have been identified according to the research problem the following question:
What are the mechanisms of visual attractions in the interior spaces and the current research aims to Recruitment mechanisms of visual attractions in the design of interior spaces as determined by three research limits are:
• Reduce the objective: the mechanics of visual attraction.
• Reducing the spatial: S

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