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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
Fri Jan 16 2009
Journal Name
National Journal Of Chemistry
Synthesis and study of the mixed ligand (phenylalanine and alanine acid) with some transition Ions
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This paper presents the synthesis and study of some new mixed-liagnd complexes containing tow amino acids[Alanine(Ala) and phenylalanine (phe)] with some metals . The results products were found to be solid crystalline complexes which have been characterized by using (FT-IR,UV-Vis) spectra , melting point, elemental analysis (C.H.N) , molar conductivity and solubilty The proposed structure of the complexes using program , chem office 3D(2000) . The general formula have been given for the prepared complexes : [M(A-H)(phe-H)] M(II): Hg , Mn ,Co , Ni , Cu ) , Zn , Cd(II) . Ala = Alanine acid = C3H7NO2 Phe = phenylalanine = C9H11NO2

Publication Date
Thu Jan 01 2009
Journal Name
National Journal Of Chemistry
Synthesis and study of the mixed ligand (phenylalanine and alanine acid) with some transition Ions .
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Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evaluation the Effect of Catechins Extract Intake for Iraqi Male Patients With Cardiovascular Diseases CVD
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  Cardiovascular diseases CVD are responsible for the majority of death in many countries, the term cardiovascular disease CVD includes several diseases such as: coronary artery diseases (angina, myocardial infaraction MI, atherosclerosis) and stroke. These diseases cause elevation of TC, TG, LDL, VLDL, and MDA levels in plasma and decrease of HDL levels and PON activity in plasma, because of elevation in lipid peroxidation (LPO) activity.  Catechins is a water extract of green tea composed of: (-)epicatchin EC, ECG, EGC, EGCG, (+) catechin C and GC, these compounds play great roles against chronic diseases such as CVD. The effect of catechins extract on the preceding biochemical parameters was investigated in 40 volunteer male

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Publication Date
Thu Aug 01 2019
Journal Name
مجلة العلوم الاقتصادية والإدارية
Improving" Jackknife Instrumental Variable Estimation method" using A class of immun algorithm with practical application
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Improving" Jackknife Instrumental Variable Estimation method" using A class of immun algorithm with practical application

Publication Date
Wed Feb 12 2025
Journal Name
Journal Of Physical Education
Agility and its relationship with of scoring accuracy for young footballers aged (14-16) years
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Publication Date
Sat Feb 01 2020
Journal Name
Journal Of Southwest Jiaotong University
The Dynamics of an Eco-Epidemiological Model with Allee Effect and Harvesting in the Predator
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The aim of this study was to propose and evaluate an eco-epidemiological model with Allee effect and nonlinear harvesting in predators. It was assumed that there is an SI-type of disease in prey, and only portion of the prey would be attacked by the predator due to the fleeing of the remainder of the prey to a safe area. It was also assumed that the predator consumed the prey according to modified Holling type-II functional response. All possible equilibrium points were determined, and the local and global stabilities were investigated. The possibility of occurrence of local bifurcation was also studied. Numerical simulation was used to further evaluate the global dynamics and the effects of varying parameters on the asymptotic behavior of

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Publication Date
Fri Mar 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Integration The Cost Techniques with Balanced Scorecard for The Purposes of Measuring and Evaluating Performance
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The effective application of the method of measuring and evaluating performance according to the Balanced  Scorecard the need for an information system a comprehensive and integrated for internal and external environment, Which requires the need to develop accounting information system in general and cost management information systems to suit the particular requirements of the environment in terms of the development of modern methods of measurement to include the use of some methods that have proven effective in measuring and evaluating performance.

The research problem in need of management to develop methods of measuring and evaluating performance through the use of both financial measures and non

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Publication Date
Fri Jul 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Structural Study of Some Mo(II) Carbonyl Complexes with Triazole and Oxadiazole Derivative
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 A new carbonyl complexes of triazole and oxadiazole were synthesized. These complexes were identified and their structural geometric were suggested by using FT-IR and UV-Vis spectra, conductivity measurements and other chemical and physical properties.   The spectra data (FT-IR, UV, Vis.) with the substantial aid of group theoretical calculations gave so many evidences for the proposed geometries and the type of bonding of these compounds

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Publication Date
Wed Jan 20 2021
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Sera Level and Polymorphism of Interleukin-33 Gene in Iraqi Females Patients with Breast Cancer
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Interleukin-33 [IL-33] is a specific ligand for the ST2 receptor, and a member of the
IL-1 family. It is a dual-function protein that acts both as an extracellular alarmin cytokine,
and an as an intracellular nuclear factor participates in maintaining barrier function by
regulating gene expression of IL-33 modulating tumor growth and anti-tumor immunity in
cancer patients. The present study aimed to investigate the role of IL-33 serum level and gene
polymorphism in Iraqi women with breast cancer. Materials and methods: Blood samples
were collected from 66 Iraqi patient women diagnosed with breast cancer, which were divided
into two groups: pre-treatment [PT] and under treatment with chemotherapy [UTC] patients in

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
MECHANICAL DEGRADATION OF HIGH MOLECULAR WEIGHT POLYMER WITH SURFACTANT ADDITION IN A ROTATING DISK APPARATUS
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Mechanical degradation hampers the practical usage of polymers for turbulent drag reduction
application. Mechanical degradation refers to the chemical process in which the activation energy of
polymer chain scission is exceeded by mechanical action on the polymer chain, and bond rupture
occurs. When a water-soluble polymer and surfactant are mixed in water solution, the specific structures
(aggregates) are formed, in which polymer film is formed around micelle. In this work, Xanthan gum (XG) –
Sodium lauryl ether sulfate (SELS) complex formation and its effect on percentage viscosity reduction
(%VR) was studied. It was found that SELS surfactant reduced the mechanical degradation of XG much
more efficiently than th

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