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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 Dec 11 2018
Journal Name
Baghdad Science Journal
Effect of irrigation by saline magnetized water on seed germination and seedling growth of wheat Triticum aestivum
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The effect of saline magnetized water irrigation on seed germination and seedling growth of wheat cultivar Iraq were studied. Irrigation water was supplemented with different levels of Sodium chloride 6, 12 or 18 mmhos/ cm in addition control treatment, and passed through a proper magnetic felid with 1000, 1250, 1500 or 2000 gaus in addition control treatment. The results showed significantly stimulated shoot development and led to the increase of germination, seedling emergence, area leaf, length of shoot and root and fresh and dry weight compared to the controls. Results also showed significant interaction between saline water and magnetized water. So, using magnetic treatment of saline water could be a promising technique

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Publication Date
Wed Apr 10 2024
Journal Name
Euphrates Journal Of Agriculture Science
Effect of irrigation levels and organic matter on quality chracteristics of chilli pepper under organic farming system
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Publication Date
Tue Nov 09 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The effect of solvency on the investments of insurance companies: applied research in the National Insurance Company
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The research aims to demonstrate the impact of the acceptable solvency of the National Insurance Company on the investment activity in it, as the research assumes the existence of a statistically significant relationship between the acceptable solvency variable and the investment variable, and the researcher took the National Insurance Company as a place to conduct the research, as it is the first insurance company Watania was established in the fifties of the last century, and it has a long history in the practice of investment activity, and the company’s financial statements for the period from (2010-2019) were relied on, and the annual reports issued by the company as well as records are tools for gathering information, and

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Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of Disinfection on Some Properties of Heat-Vulcanized Maxillofacial Silicone Elastomer Reinforced by Nano Silicone Dioxide
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Background: The daily cleaning routine of the silicone maxillofacial prostheses by the patient may cause some alteration in the materials properties. The purpose of the present study was to investigate the effect of different disinfection procedures on some properties of silicon dioxide reinforced Cosmesil M511 HTV maxillofacial silicone. Materials and Methods: One hundred and sixty (160) specimens were prepared by mixing 5% SiO2 nano particles and 0.5% intrinsic cream color into the silicone polymer according to manufacturer's instructions. Specimens were divided into 4 groups according to the performed test (tear strength, surface hardness, surface roughness and color) with 40 specimens each. Each group was further subdivided according to

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Publication Date
Mon Jul 21 2014
Journal Name
Sensors
Reduction of the Dimensionality of the EEG Channels during Scoliosis Correction Surgeries Using a Wavelet Decomposition Technique
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This paper presents a comparison between the electroencephalogram (EEG) channels during scoliosis correction surgeries. Surgeons use many hand tools and electronic devices that directly affect the EEG channels. These noises do not affect the EEG channels uniformly. This research provides a complete system to find the least affected channel by the noise. The presented system consists of five stages: filtering, wavelet decomposing (Level 4), processing the signal bands using four different criteria (mean, energy, entropy and standard deviation), finding the useful channel according to the criteria’s value and, finally, generating a combinational signal from Channels 1 and 2. Experimentally, two channels of EEG data were recorded fro

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Publication Date
Sun Apr 17 2016
Journal Name
جلة ابن الهيثم للعلوم الصرفةم
isolation and partial purification of cell wall lipopolysaccharides of pseduomonas areuginosa and using it as Vaccine it
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Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Classification of Arabic Alphabets Using a Combination of a Convolutional Neural Network and the Morphological Gradient Method
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The field of Optical Character Recognition (OCR) is the process of converting an image of text into a machine-readable text format. The classification of Arabic manuscripts in general is part of this field. In recent years, the processing of Arabian image databases by deep learning architectures has experienced a remarkable development. However, this remains insufficient to satisfy the enormous wealth of Arabic manuscripts. In this research, a deep learning architecture is used to address the issue of classifying Arabic letters written by hand. The method based on a convolutional neural network (CNN) architecture as a self-extractor and classifier. Considering the nature of the dataset images (binary images), the contours of the alphabet

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Publication Date
Fri Dec 15 2017
Journal Name
Journal Of Baghdad College Of Dentistry
Determination of Implant Primary Stability: A Comparison of the Surgeon’s Tactile Sense and Objective Measurements
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Background: Evaluation and measurement of primary stability could be achieved by several methods, including the resonance frequency analysis (RFA) and implant insertion torque (IT) values. The need for a sufficient primary stability, guaranteed by an adequate insertion torque and implant stability quotient values, increased its importance mainly in one stage implants or in immediate loading protocols. The aims of this study was to find if there is a correlation between the peak insertion torque (PIT) and ISQ values of implants inserted in the jaws of different bone quality which regarded as two important clinical determinant factors for prediction of implant primary stability, and to evaluate and compare whether an experienced clinician cou

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Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Study The effect of central ion to the dithene complexes on spectral shifting of saturable absorber band
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In this work dithine complexes prepared from dithiol benzil ligand and central ion to the Ni,Pd,Pt, element the ligand and complexes have been investigated using FTIR spectrophotometer and uv-vis-NIR spectral reigns show higher intensity represents the ?-?* transition in the chromopher cycle .These absorption which appear in visible and near IR spectral regions ,According to the complexes of one group ,the spectral shifting due to the change of central ion has been found to be related to atomic number of central ion .This shifting is increased while decreasing the central ion atom number These complexes have been implemented in Nd+2:YAG cavity because each posses resonant absorption band near Nd+2:YAG, Nd+2:Glass emitting at (106

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Publication Date
Sun Jan 01 2023
Journal Name
The Egyptian Journal Of Hospital Medicine
The Effect of a Program Using Auxiliary Tools to Improve The Long Passing Skill of Football Juniors
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