Preferred Language
Articles
/
joe-2040
Numerical Simulation of 3D- Flow Structure and Heat Transfer for Longitudinal Riblet Upstream of Leading Edge Endwall Junction of Nozzle Guide Vane
...Show More Authors

The simulation have been made for  3D flow structure and heat  transfer with and without

longitudinal riblet upstream of leading edge vane endwall junction of first stage nozzle guide vane .The research explores concept of weakening the secondary flows and reducing their harmful effects.Numerical investigation involved examination of the secondary flows ,velocity and heat transfer rates by solving the governing equations (continuity, Navier -stokes and energy equations ) using the known package FLUENT version (12.1).The governing equations were solved for three dimentional, turbulent flowe, incompressible with an appropriate turbulent model (k-ω,SST) .The numerical solution was carried out for 25 models of V-groove riblet with wide ranges of height (h) and space (s). The results indicated that, the riblet endwall junction was a powerful tool for controlling the flow structure, reducing secondary flow formation,and elimination the effect of heat transfer at leading edg and passage . The drag reduction produced by riblet was proportional with their height and space. V-groove riblet with dimension of (h=1.35mm and s=2.26mm) was found to be the most effective in reduction of drag (2.7%) and heat transfer (21%) so it was selected as an optimum dimension of riblet model. The results also showed that the drag reduction produced by riblet was proportional to their size. The riblet model had a great effect in elimination spanwise ,pitchwise velocities ,but strength the streamwise velocity .At leading edge ,the effect of secondary flow was extended up to 23% from span height and 35% upstream leading edge .The riblet model caused an increase in momentom at a region very close to leading edge and to move stagnation point very close to the leading edge.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Mar 28 2003
Journal Name
Journal Of Engineering
STABILITY OF UNREINFORCED AND REINFORCED EMBANKMENTS ON SOFT SOILS
...Show More Authors

Publication Date
Wed Jun 03 2020
Journal Name
Political Sciences Journal
Transitional justice: a study of the concept and mechanisms
...Show More Authors

The concept of transitional justice is newly emerging, as it was mainly associated with addressing issues of serious breaches and abuses of human rights during conflicts and situations resulting from violence and the use of force in societies that are in the process of democratization, as transitional justice aims primarily to restore civil peace and rebuild institutions The state needs multidimensional justice: a judicial system that achieves the rule of law, corrective restoration of the wounds of the past, and a distributive characteristic of the redistribution of wealth.

View Publication Preview PDF
Crossref
Publication Date
Sun Jan 27 2019
Journal Name
Journal Of The College Of Education For Women
Jews and their role in the heritage of Baghdadi
...Show More Authors

The research sheds light on an important religious sect that played a fundamental role in the structure of the Iraqi society in general and the Baghdadi society in particular, in which the Jews in general and the Jewish women in particular played an active role in the culture and heritage of Baghdadi society. The educational, cultural and artistic activity of Jewish literacy is a model for study.

View Publication Preview PDF
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
PAPR Reduction of OFDM Signals Using Clipping and Coding
...Show More Authors

The problem of the high peak to average ratio (PAPR) in OFDM signals is investigated with a brief presentation of the various methods used to reduce the PAPR with special attention to the clipping method. An alternative approach of clipping is presented, where the clipping is performed right after the IFFT stage unlike the conventional clipping that is performed in the power amplifier stage, which causes undesirable out of signal band spectral growth. In the proposed method, there is clipping of samples not clipping of wave, therefore, the spectral distortion is avoided. Coding is required to correct the errors introduced by the clipping and the overall system is tested for two types of modulations, the QPSK as a constant amplitude modul

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Mar 19 2020
Journal Name
Systematic Review Pharmacy
Synthesis and Biological Activity of Some New Thiazolidinone Derivatives
...Show More Authors

The compound [G1] was prepared from the reaction of thiosemicarbazide with para-hydroxyphenylmethyl ketone in ethanol as a solvent. Then by sequence reactions prepared [G2] and [G3] compounds. The compound [G4] reaction with ethyl acetoacetoneto synthesized compound [G6] and acetyl acetone to synthesized compound [G5]. Reaction the [G3] with two different types of aldehydes in the present of pipredine to form new alkenes compounds [G7]and [G8].The compound [G3] reacted with hydrazine hydrate to formation[G4] with present the hydrazine hydrade 80% in (10) ml of absolute ethanol. Latter the compound [G4]reacted with different aldehydes with present the glacial acetic acid and the solvent was ethanol to formed the Schiff bases compounds[G9] an

... Show More
Publication Date
Sat May 01 2021
Journal Name
Journal Of Engineering
Variation Orders and Their Effects of Erbil Governorate Projects
...Show More Authors

Variation order plays an important role in calculating the final cost and time. The paper aims to determine the causes of variation orders in projects performed between 2007-2014 in Erbil governorate projects. Data was collected from contract documents. Performed in the Erbil governorate projects from 2007-2014. The study seeks to identify the most significant causes of delays by assessing the common causes of delays in terms of frequency, severity and 

important indices of owners, consultants and contractors related to&n

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Fri Jul 01 2016
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
ISOLATION AND IDENTIFICTION OF FUNGI INFECTING ALOE VERA PLANT
...Show More Authors

    This study included isolation and identification of the fungi associated with Aloe vera (L.) in nurseries and plant gardens. The results showed that the fungi Alternaria alternata, Fusarium oxysporum, Fusarium solani, Nigrospora oryzae, Cladosporium herbarum, Stemphylium botryosum, Aspergillus niger, Penicillium sp. were isolated from the diseased leaves of Aloe vera showing spots and blight symptoms. The percentages of disease incidence in March, Jun and August were found to be 5, 50 and 60 %, respectively. Pathogenicity test of Alternaria alternata, Fusarium oxysporum, Nigrospora oryzae and Cladosporium herbarum showed that disease index were 50, 25,25and 12.5 %,

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Buckling Analysis of Stiffened and Unstiffened Laminated Composite Plates
...Show More Authors

The present study focused mainly on the analysis of stiffened and unstiffened composite laminated plates subjected to buckling load. Analytical, numerical and experimental analysis for different cases has been considered. The experimental investigation is to manufacture the laminates and to find mechanical properties of glass-polyester such as longitudinal, transverse young modulus, shear modulus. The compressive test was carried to find the critical buckling load of plate. The design parameters of the laminates such as aspect ratio, thickness ratio, boundary conditions and number of stiffeners were investigated using high order shear deformation theory (HOST) and Finite element coded by ANSYS .The main conclusion was the buckling load c

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Feb 13 2023
Journal Name
Journal Of Educational And Psychological Researches
Empathy of University Students with Gender and Specialization Variables
...Show More Authors

Abstract

This study aims to identify the empathy of University Students, as well as the significant differences in sympathy in terms of gender and specialization. To achieve the aims of the study, a scale of empathy was administered to a sample of (450) students collected randomly from Baghdad university. The results showed that the study sample has a level of empathy. There is a significant difference between males and females in empathy, in favor of the female students. There is no significant difference in empathy in terms of specialization (scientific, humanities), and the interaction between males and females. The study came out with a number of recommendations and suggestions. 

View Publication Preview PDF
Publication Date
Thu Jun 01 2023
Journal Name
Baghdad Science Journal
Role of IL-37 and Dectin-1 during Toxoplasmosis
...Show More Authors

Toxoplasmosis is a parasitic infection that triggers immune cells to produce cytokines and inflammatory mediators that are responsible for abnormal or aborted immune responses. This study highlights the evaluation of the Dectin-1 receptor and cytokine IL-37 in the serum of 80 patients who had miscarried in the first trimester and were infected with toxoplasmosis, as well as 40 pregnant women in the first trimester who had a successful pregnancy (control groups). The serum was first screened for the T. gondii IgM and IgG antibodies by an enzyme-linked immunosorbent assay (ELISA) and then the serum levels of IL-37 and Dectin-1 were determined. The results showed that the serum level of Dectin-1 was significantly increased in anti-

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (1)
Scopus Crossref