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Experimental and Numerical Research on Flow-Induced Vibration in Valves
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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).

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Publication Date
Sun Apr 03 2016
Journal Name
Journal Of Educational And Psychological Researches
The effect of a counseling program to develop the skills of friendship among introverts children
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Some children are suffering from introversion in kindergartens , so it must be confront and obviated by specialists because it will inevitably lead to unsatisfactory results reflect negatively on the individual and the community together . And the introvert child is a miserable child incapable of social interaction or give - and - take with colleagues , lack of integration of the child to life leads to the obstruction of  participation with his peers in various activities.     Introversion  causes a real emotional deficit to the children of kindergartens which limits of possibility of their intellectual development and mental growth and that because of their isolation and poor focus in education

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Publication Date
Sat Jan 01 2022
Journal Name
Psychological Science
أثر استراتيجية الياءات الخمس في تنمية مهارات تشكيل الاشغال المعدنية
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هدف البحث الحالي الى التعرف على اثر استراتيجية الياءات الخمس في التميه مهارة الاشغال المعدنية ، وتبلورت مشكلة البحث عن السؤال الاتي هل يوجد دور لاستراتيجية الياءات الخمس في تنمية مهارة الاشغال المعدنية لدى طلبة كلية التربية الاساسية ، عينة البحث شملت 60 طالب، اما الاستنتاجات التي توصل اليها البحث - تسهم استراتيجية في زيادة الدافعية نحو التعلم , لما توفره فيه من الجو التفاعلي الذي كسر الجمود مما انعكس ايجابياً

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Publication Date
Tue Jan 12 2021
Journal Name
Arab Science Heritage Journal
الفاظ الحــــــــــــــــــرب ودلالاتها في الشعر العباسي شعر صــــــر در أنموذجــــــــــــــــــا
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      That art and poetic creativity is not associated with a certain time and place and that artistic inspiration is a gift from God loved to a group of individuals so that their experiences be simulated speaking to the insides of the human self and that the creativity of the artist poet lies in the purpose of what is familiar and accepted and mocked for this purpose to

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Publication Date
Wed Feb 06 2019
Journal Name
Journal Of The College Of Education For Women
من اعجازات القرآن الكریم الأصل العضوي للنفط في سورة الاعلى
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The energy consider generally and specifically the petroleum energy
from the prior requirement of the population and nations, and the basics of the
survival of mankind and all the challenges for the sake of continuum, so
without this energy the life of ankind being varied, so far the life is still as a
fact on the planet earth, and suppose the life may continue as the willing of
Allah ,that the events and the standards and the degree of development is still
as it is, in another word no any technical developments and no any
entertainment no transportation and also there is no demographic domination
for the whole lands belonging to Allah, certainly no way to talk more on what
we and the others knew, what is the g

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Publication Date
Tue Oct 05 2021
Journal Name
Arab Science Heritage Journal
اسرة بنو الشحنة ودورها في الحياة الادارية خلال العصر المملوكي
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The sultans of the Mamluk state, since the establishment of their state in the year   AD, were keen to bring scholars closer to them, and entrusted the vra in the state.  ;  This is because of their confidence in

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Publication Date
Sat Jan 12 2019
Journal Name
Journal Of The College Of Education For Women
STUDY THE CHARACATERISTIC OF SOILS TO DETERMINE SOME TYPES OF LANDS DEGRADATION FOR MAHMUDIYA DISTRICT
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This study comprised three traverses extending parallel through the Northern, Central and Southern Mahmudiya districts, and perpendicular to the course of the Euphrates River. They were identified to collect (15) soil samples and some water samples as distributed within the land cover classes of the study area. Those classes were determined by visual interpretation and supervised classification for Landsat (TM) images obtained in August/2007. The digital classification was based on Maximum Likelihood method using six spectral bands excluding the thermal band. Chemical and physical laboratory analysis for the soil characteristics was performed to determine the types of land degradation in the study area.
The results showed that the hig

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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
IQ TEST STANDARDIZATION OF MARTEN LOTHER JOHAN WITH CHILDREEN OF THE SEVEN YEAR
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This study aimed to IQ test standardization of Marten Lother Johan which used with childreen of the tow  stage at primary schools who aged (7) years old in Baghdad (Resafaa and Kharh).

 The importance of this study are :

1-The  importance of childhood and its role to develop the personality.

2-The importance of this age as the child will exposure to different kind of official teaching .

3-The capability for early detection of special category for early intervention in order to provide the necessary care .

4-Using the current test could consider as a predictive tool to screen the intelligent children .

In order to achieve the study aim, the researcher had followed the

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Publication Date
Mon Jan 23 2023
Journal Name
Arab Science Heritage Journal
المصاحبة اللفظية بين الصفة والموصوف في خطب الرسول دراسة دلالية
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There are words that are described in certain words that are not described in other words, so the relationship between two words that accompany a habit is strengthened, which leads to the emergence of a conjunction or an idiomatic expression

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Publication Date
Wed Jul 01 2015
Journal Name
Political Sciences Journal
Israeli vision of Iran's nuclear program Under Iranian - US rapprochement
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Israel is one of the countries most interested in Iran's nuclear program file, and the progress of negotiations between Iran and the six countries and will end it, as well as the nature of the relationship between Iran and the United States of America. Is determined by the Israeli vision of the nature of Iran's nuclear program Iran's policy toward Israel orientations, which does not recognize the existence of Israel. Israel, therefore, one of the countries pushing to prevent Iran from acquiring nuclear technology. However, those Israeli efforts did not succeed in achieving its objectives, the United States of America and European countries is well aware of the risk of stenosis on Iran, as well as the risks and the consequences of militar

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
نحو رؤيا استراتيجية لبناء القدرة التنافسية للاقتصاد والصناعة في العراق
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استهدفت هذه الدراسة تحليل واقع الاقتصاد العراقي على خلفية تحليل القدرة التنافسية بما يفضي الى وضع ملامح عامة لإستراتيجية بناء للقدرة التنافسية الوطنية للنهوض بالواقع الاقتصادي. وقد افترضت الدراسة ان الاقتصاد العراقي يعاني من اخفاقات شديدة في الاداء لا تتصل بطبيعته ولاتعتبر سمة اصيلة من سماته  بل هي ظرفية وطارئة رغم وجودها منذ عقود.

ان حالة الوهن المرافق للفعاليات الاقتصادية تتصل بغيا

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