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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
Wed Sep 30 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The effect of the law of amending the unified pension law No. (26) of 2019 on the size of tax revenues An applied research on a sample of Iraqi public universities: أثر تطبيق قانون التقاعد الموحد رقم (26) لسنة 2019 على حجم الايرادات الضريبية
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The contribution rate of tax revenues in the federal budget is very small compared to the rate of contribution of oil revenues and this leads to negative repercussions on the Iraqi economy and the budget becomes a prisoner of high and low oil prices, and this is a problem that needs to be studied to know the extent of the impact of economic and political decisions on the size of tax revenue and The research goal is determined in studying the effect of amending the Unified Law No (26) of 2019 on the size of annual tax revenues .                                   &

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Publication Date
Fri Dec 31 2021
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
TO WHAT EXTENT THE APPLICATION OF MALCOLM BALDRIGE OF THE COMPREHENSIVE QUALITY STANDARDS IN THE AFTER- SALES SERVICES/ APPLIED RESEARCH IN ONE OF THE PRIVATE SECTOR COMPANIES: TO WHAT EXTENT THE APPLICATION OF MALCOLM BALDRIGE OF THE COMPREHENSIVE QUALITY STANDARDS IN THE AFTER- SALES SERVICES/ APPLIED RESEARCH IN ONE OF THE PRIVATE SECTOR COMPANIES
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The aim of the research is to identify to what extent to which Malcolm Baldrige standards of total quality are applied in the after-sales services of a private sector company for electrical appliances, from the point of view of administrative leaders, in it. To achieve this aim a questionnaire has been used to measure the degree of application of Malcolm’s seven criteria for total quality, namely: (leadership, strategic planning, focus on the customer, measurement and analysis and knowledge management, focus in human resource and operation management and results of the company’s management), the research found that the company achieved a good level of the standard from the de

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Publication Date
Fri Jan 01 2016
Journal Name
International Journal Of Advanced Scientific And Technical Research
Topological Generalizations of Rough Concepts
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The importance of topology as a tool in preference theory is what motivates this study in which we characterize topologies generating by digraphs. In this paper, we generalized the notions of rough set concepts using two topological structures generated by out (resp. in)-degree sets of vertices on general digraph. New types of topological rough sets are initiated and studied using new types of topological sets. Some properties of topological rough approximations are studied by many propositions.

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Publication Date
Mon Apr 01 2013
Journal Name
International Journal Of Mathematical Archive
ON GROUPS OF GEOMETRIC FIGURES
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In this paper we introduce the basic of definitions of groups for geometric figures; we describe some of geometric figures by using the properties of groups. The classification of some geometric figures by using the properties of some algebraic structures.

Publication Date
Fri Jun 30 2023
Journal Name
Journal Of The College Of Education For Women
Knowledge purification of Kindergarten Children
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The research is concerned with the problems of knowledge purification of kindergarten children by verifying its aims, identifying of knowledge purification among the first level of kindergarten children and the second level of kindergarten children, and the differences between the males and females in the variable of knowledge purification. The research community included the children in the state and private kindergartens in Baghdad governorate, on its two sides, Karkh and Rusafa, for the six districts for the academic year 2022-2023. After making the knowledge purification test according to the scientific steps of test constructions, the test has been presented to a group of experts specialized in the field of kindergarten to ascertain

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Publication Date
Fri Mar 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Nucleation Kinetics of Ammonium Perchlorate
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Publication Date
Sun Dec 02 2018
Journal Name
Journal Of The College Of Education For Women
Psychological Views of Ibn-Aljawzi
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           The researcher found that neglecting our Arab Islamic heritage and bragging about what the West came in the field of education and psychology is common in our curriculum

So the researcher found it necessary to identify the thought of our media Arab Muslims like Ibn Al-Jawzi being a remarkable figure in the world of human thought therefore, the researcher in this research decided to identify his educational and psychological ideas and psychological emotions in his mind and methods of control and characteristics of the human soul and methods of development of the Muslim character by following the descriptive analytical approach.

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Micropropagation of kiwi Actinidia chinensis
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Shoot tip of Actinidia chinensis plant were excised and sterilized with mercuric chloride (Hgcl2) at concentration 0.1% for 5 min, then cultured on MS medium supplemented with benzeladinine BA at concentration (0.0,0.5,1.0,2.0,2.5) mg/l in multiplication stage Moreover, indole butyric acid IBA at concentration (0.0, 0.5,1.0,2.0,4.0) mg/l and (0.0,0.5,1.0,2.0) mg/l on solid and liquid solution media respectively in rooting stage were studied. All experiments have done under controlled conditions (25 ±2) Cº and 1000Lux light intensity for 16 hrs / day. Results revealed that supplementing the media with BA at concentrations 2.0 and2.5 mg/l was superior to give highest rate of shoot and number of leaves reached 5.8 /explant and 6.0 l

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Publication Date
Mon Jun 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Simulation of Wiped Film Evaporator
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A mathematical model and associated computer program were developed to simulate the steady state operation of wiped film evaporators for the concentration of glycerol-water solution. In this model, various assumptions were made to facilitate the mathematical model of the wiped film evaporator. The fundamental phenomena described were: sensible heating of the solution and vaporization of water. Physical property data were coded into the computer program, which performs the calculations of this model. Randomly selected experiments were carried out in a small scale wiped film evaporator from ALVAL COMPANY, using different concentrations of the glycerol solution (10, 30 and 50 Wt. %) for different feed rates (30, 50, 80, 100 and 120 l/h) and

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Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
The Geopolitical Problems of Eritrea
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The subject of multi- ethnics is one of the most important subjects in the study of political
geography, as multi- ethnics and its consequent problems are global geopolitical phenomena
that started early and reached its peak with the beginning of the twentieth century, because of
major changes in the political landscape that resulted by wars and led to the collapse of many
empires and major powers, a matter which led to put new political maps according to certain
considerations of the colonial powers, especially in Africa and Asia. All these things led to
the most serious challenges based on ethnic and sectarian conflict and led to the development
of geopolitical problems. Among the examples what most countries in th

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