Preferred Language
Articles
/
joe-2210
Numerical Study of Optimum Configuration of Unconventional Airfoil with Steps and Rotating Cylinder for Best Aerodynamics Performance
...Show More Authors

Numerical study of separation control on symmetrical airfoil, four digits (NACA

0012) by using rotating cylinder with double steps on its upper surface based on the computation of Reynolds-average Navier- Stokes equations was carried out to find the optimum configuration of unconventional airfoil for best aerodynamics performance. A model based on collocated Finite Volume Method was developed to solve the governing equations on a body-fitted coordinate system. A revised (k-w) model was proposed as a known turbulence model. This model was adapted to simulate the control effects of rotating cylinder. Numerical solutions were performed for flow around unconventional airfoil with cylinder to main stream velocities ratio in the range of 1 to 4 and for various positions of the steps on the airfoil from the leading edge, 0.1c, 0.2c, 0.3c, 0.4c, 0.5c for the first step and 0.5c, 0.6c, 0.7c, 0.8c for the second step with constant step depth and length of 0.03c and 0.125c respectively. Reynolds number of 700,000 which was based on the cord length (c), with angle of attacks 0, 5, 8, 10, 12, 15 degrees was considered for the assessment of the unconventional airfoil performance. The numerical investigation showed that the optimum configuration for the unconventional airfoil was found to be at velocities ratio (U/U∞=4) with the steps positions at 0.5c and 0.8c for best airfoil performance.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Jun 30 2017
Journal Name
Journal Of Engineering
Enhancing Performance of Self–Compacting Concrete with Internal Curing Using Thermostone Chips
...Show More Authors

This paper is devoted to investigate the effect of internal curing technique on the properties of self-compacting concrete (SCC). In this study, SCC is produced by using silica fume (SF) as partial replacement by weight of cement with percentage of (5%), sand is partially replaced by volume with saturated fine lightweight aggregate (LWA) which is thermostone chips as internal curing material in three percentages of (5%, 10% and 15%) for SCC, two external curing conditions water and air. The experimental work was divided into three parts: in the first part, the workability tests of fresh SCC were conducted. The second part included conducting compressive strength test and modulus of rupture test at ages of (7, 28 and 90). The third part i

... Show More
View Publication Preview PDF
Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Choose the best model to measure the impact of human capital on labor productivityIn the manufacturing sector in Iraq
...Show More Authors

In this paper all possible regressions procedure as well as stepwise regression procedure were applied to select the best regression equation that explain the effect of human capital represented by different levels of human cadres on the productivity of the processing industries sector in Iraq by employing the data of a time series consisting of 21 years period. The statistical program SPSS was used to perform the required calculations.

View Publication Preview PDF
Crossref
Publication Date
Tue Sep 01 2020
Journal Name
Baghdad Science Journal
Best Multiplier Approximation of Unbounded Periodic Functions in L_(p,∅_n ) (B),B=[0,2π] Using Discrete Linear Positive Operators
...Show More Authors

The purpose of this paper is to find the best multiplier approximation of unbounded functions in    –space by using some discrete linear positive operators. Also we will estimate the degree of the best multiplier approximation in term of modulus of continuity and the averaged modulus.

View Publication Preview PDF
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sun Mar 20 2022
Journal Name
Geotechnical Engineering And Sustainable Construction
Numerical Modeling of Circular Tunnel Alignment Under Seismic Loading
...Show More Authors

The continuous increase in population has led to the development of underground structures like tunnels to be of great importance due to several reasons. One of these reasons is that tunnels do not affect the living activities on the surface, nor they interfere with the existing traffic network. More importantly, they have a less environmental impact than conventional highways and railways. This paper focuses on using numerical analysis of circular tunnels in terms of their behavior during construction and the deformations that may occur due to overburden and seismic loads imposed on them. In this study, the input data are taken from an existing Cairo metro case study; results were found for the lateral and vertical displacements, the Peak

... Show More
View Publication
Crossref (4)
Crossref
Publication Date
Sat Feb 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Strategic Human Resource Management Practices and their reflections for Organizational Performance Improvement A Survey Study of the views of a sample of Managers Baghdad Soft Drinks company/ Zafaraniya
...Show More Authors

The aims of research is to identify the role of strategic human resource management Practices in organizational performance improvement in the Baghdad soft drinks company, as well as the implications of the results for both managers and practitioners.

In order to achieve the objectives of the research, the researcher designed questionnaire included (40) items to collect the initial data from the research sample consisting of (53) Single. In light of that has been collecting and analyzing data and test hypotheses using the statistical package for Social Sciences (SPSS21), and use a number of statistical methods to achieve the goal of the research, including the means, standard deviations and simple correla

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
The Suggested Reciprocal Relationship between Maximum, Minimum and Optimum Usable Frequency Parameters Over Iraqi Zone
...Show More Authors

In this work, the relationship between the ionospheric parameters (Maximum Usable Frequency (MUF), Lowest Usable Frequency (LUF) and Optimum working Frequency (OWF)) has been studied for the ionosphere layer over the Iraqi zone. The capital Baghdad (44.42oE, 33.32oN) has been selected to represent the transmitter station and many other cities that spread over Iraqi region have represented as receiver stations. The REC533 communication model considered as one of the modern radio broadcasting version of ITU has been used to calculate the LUF parameter, while the MUF and OWF ionospheric parameters have been generated using ASAPS international communication model which represents one of the most advanced  and accurate HF sky wave prop

... Show More
View Publication
Scopus (9)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
The Suggested Reciprocal Relationship between Maximum, Minimum and Optimum Usable Frequency Parameters Over Iraqi Zone
...Show More Authors

In this work, the relationship between the ionospheric parameters (Maximum Usable Frequency (MUF), Lowest Usable Frequency (LUF) and Optimum working Frequency (OWF)) has been studied for the ionosphere layer over the Iraqi zone. The capital Baghdad (44.42oE, 33.32oN) has been selected to represent the transmitter station and many other cities that spread over Iraqi region have represented as receiver stations. The REC533 communication model considered as one of the modern radio broadcasting version of ITU has been used to calculate the LUF parameter, while the MUF and OWF ionospheric parameters have been generated using ASAPS international communication model which represents one of the most advanced  and

... Show More
View Publication Preview PDF
Scopus (9)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Fri Mar 05 2021
Journal Name
Materials
Optimum Placement of Heating Tubes in a Multi-Tube Latent Heat Thermal Energy Storage
...Show More Authors

Utilizing phase change materials in thermal energy storage systems is commonly considered as an alternative solution for the effective use of energy. This study presents numerical simulations of the charging process for a multitube latent heat thermal energy storage system. A thermal energy storage model, consisting of five tubes of heat transfer fluids, was investigated using Rubitherm phase change material (RT35) as the. The locations of the tubes were optimized by applying the Taguchi method. The thermal behavior of the unit was evaluated by considering the liquid fraction graphs, streamlines, and isotherm contours. The numerical model was first verified compared with existed experimental data from the literature. The outcomes re

... Show More
View Publication Preview PDF
Scopus (13)
Crossref (14)
Scopus Clarivate Crossref
Publication Date
Wed Aug 21 2019
Journal Name
International Journal On Advanced Science, Engineering And Information Technology
Evaluation of the Performance of Glasphalt Concrete Mixtures for Binder Course
...Show More Authors

Crossref (3)
Crossref
Publication Date
Mon Apr 03 2023
Journal Name
Karbala International Journal Of Modern Science
Performance Estimation and System Modeling for Refractive Index Structure Constant Cn2
...Show More Authors

View Publication
Scopus (4)
Crossref (3)
Scopus Crossref