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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
Sun Aug 20 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Thermoelectric Power of Amorphous InAs Thin Films
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The thermoelectric power (S) of thermal evaporated a-InAs films

were measured in the temperature rang (303-408) K.

These films were prepared at different thickness (250,350,450) nm and treated at different annealing temperatures (303,373,423,473,523) K.

The behaviour  of the thermoelectric power  studies of these films

as  a  function  of  thickness  and  annealing  temperature  showed  the thermoelectric  power an increasing trend with annealing temperature

,whereas it decreases as the film thickness increases.

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Publication Date
Tue Oct 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Weak Essential Fuzzy Submodules Of Fuzzy Modules
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        Throughout this paper, we introduce the notion of weak essential F-submodules of F-modules as a generalization of  weak essential submodules. Also we study the homomorphic image and inverse image of weak essential F-submodules.

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Publication Date
Thu Dec 29 2016
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Chilling Imbibition on Seed Germination
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  Tomato (Lycopersicon esculentum Mill) and cucumber (Cucumis sativus L.)  seeds were imbided with water at 10°c or 4°c for 4, 8, and 16 hours before planting to study germination rate, mean germination time, and final germination percentage as well as electrolyte leakage from chilled seeds. Seeds imbided more water at 10°c compared to that at 4°c. Coefficient velocity of germination and final percent of germination decreased with the decrease of temperature and increasing time of imbibition. Germination percent under laboratory conditions was higher than that under field conditions. Also, it was found that tomato seeds were more sensitive to chilling imbibition. Electrolyte leakage increased as temperature of imbib

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Publication Date
Fri Oct 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Spectroscopic Diagnostic of Laser-Induced Zn Plasma
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The sample's physical characteristics and laser parameters impact the generation and characterization of Laser-Induced Plasma (LIP), which is a relevant phenomenon in many applications. We investigated the effect of laser energy on laser-induced Zn plasma characterization in this study. A Zn plasma with a repeating frequency of 6 Hz, a first wavelength of 1064 nm, a pulse duration of 10 ns, and a laser energy range of 300 mJ to 500 mJ was created using a Q-switched ND: YAG laser. The basic plasma properties, such as electron temperature and density, were estimated using optical emission spectroscopy (OES). The electrons' temperature was measured by the Boltzmann plot method, and the value of the electrons' temperature ranged from 1.6 eV

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Detection of Human Remain Using GPR Technique
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    In this work, animal bones with different shapes and sizes were used to study the characteristics of the ground penetrating Radar system wares reflected by these bones. These bones were buried underground in different depths and surrounding media. The resulting data showed that the detection of buried bones with the GPR technology is highly dependent upon the surrounding media that the bones were buried in. Humidity is the main source of signal loss in such application because humidity results in low signal-to-noise ratio which leads to inability to distinguish between the signal reflected by bones from that reflected by the dopes  in the media such as rock .

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of The College Of Languages (jcl)
Failure of Comedy in Waiting for Godot
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Many critics suggest that Beckett’s early plays are comic because they focus their analyses on the use comic elements. Waiting for Godot is one of Beckett’s early plays, and it has been heavily analyzed and read as a comic text partly because its subtitle is “a tragicomedy in two acts” and also because of the comic techniques used in the play. The present paper, however, attempts to read the play as a piece in which comedy fails to produce any effects on the characters who remain apparently very desperate and frustrated throughout the play. The characters perform different comic acts, but they do not really feel amused or entertained. The paper suggests that the acts these characters put on stage are only means to pass t

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Publication Date
Mon Jul 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On the Space of Primary La-submodules
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     Suppose that F is a reciprocal ring which has a unity and suppose that H is an F-module. We topologize La-Prim(H), the set of all primary La-submodules of H , similar to that for FPrim(F), the spectrum of fuzzy primary ideals of F, and examine the characteristics of this topological space. Particularly, we will research the relation between La-Prim(H) and La-Prim(F/ Ann(H)) and get some results.

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
MEASUREMENT OF TRANSMITED VIBRATION TO TRACTOR SEAT
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A field experiment was conducted at experimental field of Mechanization Agriculture , the
College of Agriculture , Abu – Ghraib , University of Baghdad .To measure transmitted vibration to
seat tractor during operation tillage , mold board plow with New Holland 66-S- 80 tractor as one
machinery unit , Soil was treated at soil constant moisture ( 18 – 20 % ) with two depths of plowing
(15 and 20 cm ) and three speed of tractor 2.0 , 3.5, 6.8 km / h . Three main dimensions in seat
tractor measurement vertical, longitudinal and lateral acceleration. Split plot design under
completes block design with three replicates

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Publication Date
Thu Apr 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evaluation of Asprosin Hormone in Hypothyroidism Patients
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Asprosin was a novel adipokine that was released by white adipose tissue. It was activated by fasting and attracted to the liver, which allowed the liver to rapidly release glucose into the bloodstream. White adipose tissue was the source of asprosin. When people go on a fast, their blood sugar levels drop, which causes levels of the hormone asprosin to rise. It does this by binding to a G-protein-coupled receptor in the liver known as OR4M1, which in turn activates a cascade that involves the G -protein-cAMP-PKA pathway. Because of this, the glucose that is stored in the liver is released.  We anticipate that by investigating the changes that occur in asprosin levels in hypothyroidism patients, we will be able to make a significant

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Publication Date
Tue Aug 03 2021
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
New Travelling Wave Solution of Burgers Equations
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     In this paper, we studied the travelling wave solving for some models of Burger's equations. We used sine-cosine method to solution nonlinear equation and we used direct solution after getting travelling wave equation.

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