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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 Jul 01 2020
Journal Name
Journal Of Engineering
Improvement the Mechanical Characteristics of Alloy Steel DIN 41Cr4 by Shot Peening
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The effects of shot peening treatment (SPT) were studied at (10,20, and 30) minutes on the rotating bending fatigue behavior and the behavior of the alloy steel DIN 41Cr4 vibrations. The hardness test, tensile test, constant amplitude fatigue tests, and the vibration measurements were performed on samples with and without cracks at room temperature (RT), also, the fracture surface was examined and analyzed by a Scanning Electron Microscope (SEM). The results of the investigations, for example, Stress to Number of cycles to failure (S-N) curves, fatigue strength improvement factor of 5% to 10%, the decreasing percentage of maximum Fast Fourier Transform (FFT) acceleration of the shot-peened condition were compared to untr

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Publication Date
Tue Nov 01 2022
Journal Name
Optik
Optical and structural characteristics of pulsed DC magnetron sputtered Ce1−xTixOy coatings
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This contribution investigates the impact of adding transition metal of Ti to CeOy samples at various concentrations referring to 0, 15.84, 24.46, 34.46, 36.23, 38.46, 45.38% and pure TiOy, correspondingly. The samples were fabricated by the magnetron sputtering technique. X-ray diffraction (XRD) configurations demonstrate the presence of α-Ce2O3 and Ce2O3 phases with increased Ti contents in the systems. X-ray photoelectron spectroscopy (XPS) experimentation confirms the purity of the S1-sample (CeO2) and the purity of the S8-sample (TiO2). Further XPS analysis reveals that Ti incorporation in the doped systems functions as a reducing agent because of the existence of α-Ce2O3 and Ce2O3 phases. Moreover, based on UV–vis spectroscopy res

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Publication Date
Fri Oct 02 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Load-deflection characteristics and force levels of coated nickel titanium orthodontic archwires
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Background: Coated archwires have been introduced to improve esthetics during orthodontic treatment. Theaim of the present study was to evaluate and compare the load–deflection characteristics and force levels of six brands of coated nickel titanium orthodontic archwires using palatal and gingival deflection. Materials and methods: Ten round wires (0.016 inch) and ten rectangular wires (0.019x0.025 inch) were obtained from each of six brands (G&H, Opal, Ortho Technology, Dany, Hubit and Astar Companies). The load-deflection properties of these archwires were evaluated by the modified bending test usinga readymade dental arch model in both palatal and gingival directions at 37°C temperature using a universal material testing machi

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Publication Date
Sun Sep 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Characteristics and pattern of organizational structure for general inspectors offices :Testing Research
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Concentrated research topic in addressing variable vital to the work of offices of inspectors general, construction and scale effectiveness and efficiency is the organizational structure, which are important as is obvious to any researcher in the management and organization and this variable would affect the exercise task supervision and inspection of financial and administrative corruption and combat efficiently, Thus this effect will be placed in the fold ability to achieve goals. That the creation of the organizational structure and requirements to achieve harmony between its properties is creating step towards success. This research aims to analyze the characteristics and style o

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Publication Date
Fri Sep 01 2017
Journal Name
Gulf Journal Of Oncology
Clinical and Pathological Characteristics of Triple Positive Breast Cancer among Iraqi Patients
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Background: Breast cancer is the most common malignancy affecting the Iraqi population and the leading cause of cancer related mortality among Iraqi women. It has been well documented that prognosis of patients depends largely upon the hormone receptor contents and HER-2 over expression of their neoplasm. Recent studies suggest that Triple Positive (TP) tumors, bearing the three markers, tend to exhibit a relatively favorable clinical behavior in which overtreatment is not recommended. Aim: To document the different frequencies of ER/PR/HER2 breast cancer molecular subtypes focusing on the Triple Positive pattern; correlating those with the corresponding clinico-pathological characteristics among a sample of Iraqi patients diagnosed with th

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Publication Date
Mon Jul 01 2024
Journal Name
Journal Of Optics
Optical and structural characteristics of carbon quantum dots manufacturing by electrochemical method
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Electrochemical method was used to prepare carbon quantum dots (CQDs). Size of matter was nature when evaluate via X-ray diffraction (XRD). A distinct peak at 2θ equal to 31.6° and three other small peaks at 38.28°, 56.41° and 66.12° were observed. The measures of Fourier Transform Infrared Spectroscopy (FTIR) showed the bonds in the transmittance spectrum are manufactured with carbon nanostructures in view. The first peaks are the O–H stretching vibration bands at (3417 and 2922) cm−1, (C–O–H at 1400, and 1317) cm−1, (C–H), (C=C), (C–O–H), (C=O), and (C–O) bonds at 2850, 1668, 1101, and 1026 cm−1 sequentially. The transmission electron microscopy (TEM) results presented that the spherical CQDs are in shape and on a

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Publication Date
Sun Dec 01 2019
Journal Name
Materials Science-poland
Electrical and thermal characteristics of MWCNTs modified carbon fiber/epoxy composite films
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Abstract<p>To enhance interfacial bonding between carbon fibers and epoxy matrix, the carbon fibers have been modified with multiwall carbon nanotubes (MWCNTs) using the dip- coating technique. FT-IR spectrum of the MWCNTs shows a peak at 1640 cm<sup>−1</sup> corresponding to the stretching mode of the C=C double bond which forms the framework of the carbon nanotube sidewall. The broad peak at 3430 cm<sup>−1</sup> is due to O–H stretching vibration of hydroxyl groups and the peak at 1712 cm<sup>−1</sup> corresponds to the carboxylic (C=O) group attached to the carbon fiber. The peaks at 2927 cm<sup>−1</sup> and 2862 cm<sup>−1</sup> ar</p> ... Show More
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Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
Investigation of Doppler broadening Compton scattering for aluminum element at different angles
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Publication Date
Sat Jan 01 2022
Journal Name
3rd International Scientific Conference Of Alkafeel University (iscku 2021)
Simulation and investigation of the ICP plasma torch’s electrical and thermal properties
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Publication Date
Sat Dec 31 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Experimental Investigation of Mass Transfer for Copper Reduction by Weight Difference Technique
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An experimental analysis was included to study and investigate the mass transport behavior of cupric ions reduction as the main reaction in the presence of 0.5M H2SO4 by weight difference technique (WDT). The experiments were carried out by electrochemical cell with a rotating cylinder electrode as cathode. The impacts of different operating conditions on mass transfer coefficient were analyzed such as rotation speeds 100-500 rpm, electrolyte temperatures 30-60 , and cupric ions concentration 250-750 ppm. The order of copper reduction reaction was investigated and it shows a first order reaction behavior. The mass transfer coefficient for the described system was correlated with the aid of dimensionless groups as fo

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