Preferred Language
Articles
/
joe-2256
Effect of Design Parameters and Support Conditions on Natural Frequency of Pipe Excited by a Turbulent Internal Flow
...Show More Authors

In this study, the effect of design parameters such as pipe diameter, pipe wall thickness, pipe material and the effect of fluid velocity on the natural frequency of fluid-structure interaction in straight pipe conveying fully developed turbulent flow were investigate numerically,analytically and experimentally. Also the effect of support conditions, simply-simply and clamped-clamped was investigated. Experimentally, pipe vibrations were characterized by accelerometer mounted on the pipe wall. The natural frequencies of vibration were analyzed by using Fast Fourier Transformer (FFT). Five test sections of two different pipe diameters of 76.2
mm and 50.8 mm with two pipe thicknesses of 3.7 mm and 2.4 mm and two pipe materials,stainless steel and polyvinyl chloride PVC in the range of Reynolds numbers from 4*104 to 5*105 were studied. Mathematically, the governing continuity and momentum equations were solved numerically by using the finite volume method to compute the characteristics of two dimensional turbulent flow. The dynamics of a pipe conveying fluid was described by the Transfer Matrix Method (TMM) which is provides a numerical technique for solving the equations of pipe vibrations for simply-simply and clamped supports. The results showed that,the natural frequencies increase with pipe diameter increase and the natural frequencies slightly increases with pipe wall thickness increase. Also, the natural frequencies in clamped-clamped supported pipe are higher than those in simply-simply supported pipe.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Micro and Nano Material on Critical Heat Flux (CHF) Enhancement
...Show More Authors

The Nano materials play a very important role in the heat transfer enhancement. An experimental investigation has been done to understand the behaviors of nano and micro materials on critical heat flux. Pool boiling experiments have used for several concentrations of nano and micro particles on a 0.4 mm diameter nickel chrome (Ni-Cr) wire heater which is heated electrically at atmospheric pressure. Zinc oxide(ZnO) and silica(SiO2) were used as a nano and micro fluids with concentrations (0.01,0.05,0.1,0.3,0.5,1 g/L), a marked enhancement in CHF have been shown in the results for nano and micro fluids for different concentrations compared to distilled water. The deposition of the nano particles on the heater surface was the rea

... Show More
View Publication Preview PDF
Publication Date
Thu Nov 21 2019
Journal Name
Al-kindy College Medical Journal
Investigate The Different Effect Of Nicotine On H460 And H441 Lung Cells Viability
...Show More Authors

Background: Nicotine is the foremost chemical constituent responsible for addiction in tobacco products, in the non-ionized condition can be easily absorbed via epithelial tissue of the lung, the mouth, the nose  and across the skin

Objective:The study examines the harmful effect of   the nicotine which is an important component of cigarette in vitro.

Type of the study: Cross-sectional study.

Methods: Examines the harmful effect of   the nicotine which is an important component of cigarette in vitro by using two types of lung cancer cell lines (H460 TP53+/+, H441 TP53-/-).

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Mar 01 2016
Journal Name
Optics Communications
Temperature effect on nonlinear refractive indices of liquid crystals in visible and NIR
...Show More Authors

View Publication
Scopus (12)
Crossref (11)
Scopus Clarivate Crossref
Publication Date
Thu Apr 01 2021
Journal Name
Biochemical And Cellular Archives
Design, Synthesis and Antibacterial Evaluoation of mutual Prodrugs of Antioxidants With Different quinolone Antibiotics
...Show More Authors

Scopus (3)
Scopus
Publication Date
Sun Mar 12 2017
Journal Name
Al-academy
The reality of Figure and content in the design of logos, civil society organizations
...Show More Authors

Civil society organizations in Iraq have become a community hard case dispensable as the link between the state institutions and their leaders, and between citizens of different orientations and age groups, as it represents the diversity of the terms of reference and understanding of the laws and standards of Universal Declaration of Human Rights, which requires governments to provide supplies president of its citizens to live in dignity, direct and Msasha in the life of society and the dictates we scientific our role in achieving scientific benefit and transfer of expertise to the community has become imperative for the researcher to campaign in the midst of the scientific research of the slogans of those or

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
Design and Analysis of Electro-Hydraulic Servo System for Speed Control of Hydraulic Motor
...Show More Authors

In this study, the electro-hydraulic servo system for speed control of fixed displacement hydraulic motor using proportional valve and (PID) controller is investigated theoretically ,experimentally and simulation . The theoretical part includes the derivation of the nonlinear mathematical model equation of (valve – motor ) combination system and the derivation of the transfer function for the complete hydraulic system , the stability test of the system during the operation through the transfer function using MATLAB package
V7.1 have been done. An experimental part includes design and built hydraulic test rig and simple PID controller .The best PID gains have been calculated experimentally and simulation, speed control performance te

... Show More
View Publication Preview PDF
Crossref (7)
Crossref
Publication Date
Mon Jun 01 2015
Journal Name
المؤتمر العلمي التخصصي الحادي والعشرون لكلية التربية/ الجامعة المستنصرية 22-23 نيسان 2015 الفيزياء
Computer Simulations of Imaging a Dirac Delta Function by a Ground-Based Optical Telescope
...Show More Authors

Two- dimensional numerical simulations are carried out to study the elements of observing a Dirac point source and a Dirac binary system. The essential features of this simulation are demonstrated in terms of the point spread function and the modulation transfer function. Two mathematical equations have been extracted to present, firstly the relationship between the radius of optical telescope and the distance between the central frequency and cut-off frequency of the optical telescope, secondly the relationship between the radius of the optical telescope and the average frequency components of the modulation transfer function.

Preview PDF
Publication Date
Wed Sep 30 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The added value of internal audit and its role in achieving independence and responsibility: applied research in the Rafidain State Company for Dams implementation
...Show More Authors

The added value of internal audit greatly contributes to adding value to the institution, but most departments of economic units in Iraq neglected the role of internal audit and the added value that can be achieved by those institutions, since the term added value of internal audit is a relatively vague term from the premise that what cannot be measured is difficult Determine it, and perhaps descriptive standards for it is the extent of compliance with international auditing standards (IIA).

The research aims to study the procedures and results of auditing to verify that they have given an added value to the audit with a positive impact, develop its aspects and research, identify deficiencies for the audi

... Show More
View Publication Preview PDF
Publication Date
Tue Jun 30 2015
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Evaluation the fermentation capacity of commercial Baker′s yeast and effect of the salt concentration on breadLeavening.: Evaluation the fermentation capacity of commercial Baker′s yeast and effect of the salt concentration on breadLeavening.
...Show More Authors

This qualitative study was conducted on eight types of commercial baking yeast which available in local markets to estimate their fermentation activity as affecting the Bread industry and the impact of the salt added to DoughLeavening, The results showed a great variation in the fermentation capacity of yeast samples (their role in swelling the dough), most notably the sample value Y3 and least sample Y7 and reached 80% and 20% respectively, and the value of Leavening by using the two types of yeast with addition of three levels of salt (0 , 1 and 2%) have 20.0 , 19.7 and 15.7 of the sample Y3, compared with 10.5 , 10.3 and 8.8 of the sample Y7 for each of the levels of salt respectively, reflect

... Show More
View Publication Preview PDF
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Water Flow Visualization And Velocity Measurement Using Hydrogen Bubble Generation Technique In Low Speed Open Channel
...Show More Authors

Visualization of water flow around different bluff bodies at different Reynolds number ranging (1505 - 2492) was realized by designing and building a test rig which contains an open channel capable to ensure water velocity range (4-8cm/s) in this channel. Hydrogen bubbles generated from the ionized water using DC power supply are visualized by a light source and photographed by a digital camera. Flow pattern around a circular disk of (3.6cm) diameter and (3mm) thickness, a sphere of (3.8cm) diameter and a cylinder of
(3.2cm) diameter and (10cm) length are studied qualitatively. Parameters of the vortex ring generated in the wake region of the disk and the separation angle of water stream lines from the surface of the sphere are plott

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