Preferred Language
Articles
/
alkej-347
Experimental and Numerical Research on Flow-Induced Vibration in Valves
...Show More Authors

Abstract  

All central air conditioning systems contain piping system with various components, sizes, material, and layouts. If such systems in operating mode, the flow in piping system and its component such as valves can produce severe vibration due to some flow phenomenon’s. In this research, experimental measurements and numerical simulation are used to study the flow-induced vibration in valves. Computational fluid dynamics (CFD) concepts are included with one-way and two-way fluid-structure interaction concepts by using finite element software Package (ANSYS 14.57). Detection analysis is performed on flow characteristics under operation conditions and relations with structural vibration. Most of real geometrical, operational, and boundary conditions are simulated to obtain best similarity with real operation conditions. Comparisons performed between experimental data and numerical results (one-way and two-way simulation) to verify the results. The main conclusion was drawn from the study that the dominant source of vibration for valve is the water pulsation in addition to amount of water hammering. In addition, the main source of water pulsation in globe valve is the vortex shedding and pressure difference between upstream and downstream of valve. The vibration amplitude was increased with increasing flow rate until to be maximum when the flow rate around 30% and then decreased until flow rate reaches to around 85% and then trends to be constant.

Keywords: Flow-induced vibration, vortex shedding, pressure pulsation, valve, finite element, ANSYS, fast Fourier transform (FFT).

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Mar 02 2022
Journal Name
Journal Of Educational And Psychological Researches
Knowledge and Attitudes toward Mental Health among People Attending PHCCs, Iraq, 2018; A cross-sectional study
...Show More Authors

Mental disorders (MDs) are a common problem in Primary Health Care Centers (PHCCs). Many people with serious MDs are challenged by symptoms and disabilities that result from the disease and by stereotypes and prejudice due to misconceptions about mental illness. This study aims at evaluating the knowledge, and attitude toward mental health concepts and services and causes of the reluctance to seek those services among people attending PHCCs. A descriptive cross-sectional study was conducted. The random sampling technique was used to include (10) of Directorates of Health (DoHs) coverage north, middle, and south of Iraq. The study was executed in (50) selected PHCs, (5) PHCCs in each DoH involved randomly selected (30) people attending th

... Show More
View Publication Preview PDF
Publication Date
Tue Aug 26 2025
Journal Name
Al–bahith Al–a'alami
EMPLOYING TWITTER IN THE U.S. PRESIDENTIAL ELECTION CAMPAIGN IN 2016: U.S. PRESIDENTIAL CANDIDATE DONALD TRUMP’S TWEETS AS A “MODEL”: (A Research Drawn from a Master’s Thesis) (An Analytical Study)
...Show More Authors

This study aimed to identify the employment of the social networking platform «Twitter» in the 2016 presidential campaign led by the Republican candidate, Donald Trump; and analyse his tweets through his personal account on «Twitter»  for the period from: 10/ 8/2016 to: 11/ 8/2016 which represents the last month of the election campaign.

The study belongs to the type of descriptive studies using the analytical method through an analysis index that includes sub-categories and other secondary categories. The research has adopted the ordinary unit of information material (tweet) as an analysis unit for this purpose.

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed May 02 2012
Journal Name
Journal Of Planner And Development
The Effect of Time and Place Dimensions on Changing the Quality Dimensions of Sizes of Cities: A Case Study (Baghdad city)
...Show More Authors

The city has normal natural state, and the man has a usual movement, change and search for the new .Also, the city has a usual change and transform in its time, place and quality (sizes)structures. The city has a solid memory diving into the past and the future and reflects The real present, and this memory has a timing layers change into real materialistic place making the city has accumulated overlapping circles which is hard to break u , and it broadcasts the lockup timing density ,in which there is no visual record precisely, it is just like((the social record)) that evaluates the un visual relationships between the components and parts of the city (community and form) in a visual quiet exhibition and transform change inside.

... Show More
View Publication
Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Effect of the professional skepticism characteristics of the auditor on audit qualit
...Show More Authors

The professional skepticism is one of the fundamental concepts necessary for practicing the audit profession, without which the auditor can not reach a reasonable assurance as to the correctness of the evidence and the information obtained by the auditing department. The auditor's possession of the characteristics of professional skepticism and his practice of professional skepticism during the audit process lead to an increase The quality of audit and thus raise the confidence of the financial community in the audit profession again after the exposure of several crises led to the loss of financial society confidence in the audit profession.

The aim of the study is to measure the impact of professional sk

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Sat Sep 30 2023
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The reflection of environmental quality costs on the evaluation of environmental performance
...Show More Authors

Abstract:

               The research aims to achieve defining the concept of environmental quality and associated costs. Studying the impact of environmental quality costs on the performance of economic units. Measuring the relationship between environmental quality and environmental performance of the units. Where the research problem is represented in the weak awareness of some economic units of the importance of environmental quality costs and their impact on evaluating environmental performance, and this leads to neglecting environmental considerations and not improving environmental performance effectively, which negatively affects the en

... Show More
View Publication Preview PDF
Publication Date
Wed Apr 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Plagiarism on the Quality of Scientific Researches “Empirical Study”
...Show More Authors

The purpose of this research is to study the quality of scientific research at the University of Baghdad in light of scientific piracy and plagiarism of research and results and attribute it to others intentionally or unintentionally. Proactive writing such as stealing ideas or synthesizing the results of one another over others and its negative impact on the quality of scientific outputs and the reputation of educational organizations through an exploratory study in the faculties of the University of Baghdad, scientific and humanitarian. As for the aims of the study, it was determined by determining the negative impact of piracy on scientific research. A Likert five-point scale was used in this research. The research community c

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Feb 25 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Impact of Using the Information Technology on The Audit Profession: A Study of the Sample of Auditor Viewpoints in Selected Arab Countries
...Show More Authors

This study aims to clarify areas of using information technology in accounting and its impact on the profession of auditors by reviewing the concept, types, areas and the importance of information technology and its implications on the audit profession as well as to clarify the extent of contribution of information technology in  developing of procedures of the audit profession and what its requirement, also this study aims to enhance the theoretical side by identifying the views of a sample of auditors in  Arab countries selected (Iraq, Syria, Jordan), for the extent of using of information technology in their work and level of their perception for the importance of that

View Publication Preview PDF
Crossref
Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The impact of production elements responsible on the environmental management system requirements of ISO 14001 - 2004 field study in the North Gas Company
...Show More Authors

Abstract

         Most of the industrial organization in the world became suffering from the problem of the pollution of the poisonous chemicals things, this urged to depend on the principle of the responsible production, because it has the positive role by dealing with these chemical things and to safe the health of the society, due to the main goal of this study is to restrict the role responsible production in accomplishing the system of the environmental management through an actual study in the northern gas company in Kirkuk province, the topic has acquired a big importance bacause there were a limited number of studies and res

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Oct 06 2013
Journal Name
Journal Of Educational And Psychological Researches
The Effect of a Behavioral-Cognitive Training Program on Problems Solving among college students in the faculty of education for women : Baghdad University
...Show More Authors

The purpose of this study was to investigate the effect of a Cognitive- Behavioral Training Program in reducing Problems Solving among a sample of education university  College Students, the study sample consisted of (50) students were randomly assigned to two groups: experimental, and control; (25) students per group, the results of (ANOVA) revealed that there were significant differences at (p < 0.05) between experimental and control group in Problems Solving level, while there were significant differences between both groups in achievement. The researchers recommended further studies on the other variables which after training students on the method of solving problems and techniques to reduce stress.<

... Show More
View Publication Preview PDF
Publication Date
Thu Oct 08 2020
Journal Name
British Journal Of Pharmacology
Protective effects of Δ<sup>9</sup>‐tetrahydrocannabinol against enterotoxin‐induced acute respiratory distress syndrome are mediated by modulation of microbiota
...Show More Authors
Background and Purpose

Staphylococcal enterotoxin‐B (SEB) is one of the most potent bacterial superantigens that exerts profound toxic effects by inducing a cytokine storm. Inhaled SEB can cause acute respiratory distress syndrome (ARDS), which is often fatal and with no effective treatments.

Experimental Approach

Efficacy of Δ9‐tetrahydrocannabinol (THC) was tested in a mouse model of SEB‐mediated ARDS, in which lung inflammation, alterations in gut/lung microbiota and production of short‐chain fatty acids (SCFAs) was measured. Gene dysregulation of lung epithelial cells was studied by transcriptome arrays. F

... Show More
View Publication Preview PDF
Scopus (44)
Crossref (43)
Scopus Clarivate Crossref