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alkej-347
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
Sat Jul 05 2003
Journal Name
الموسوعة الرقمية العربية
تقويم منهاج الفيزياء للصف الاول الثانوي في الجمهورية اليمنية
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ان الهدف من البحث هو تقويم منهاج الفيزياء للصف الاول الثانوي في الجمهورية اليمنية

Publication Date
Fri Jun 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
في تعزيز بيئة الانتاج الرشيق استخدام اسلوب S -5
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في تعزيز بيئة الانتاج الرشيق استخدام اسلوب S -5

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Publication Date
Sun Apr 06 2014
Journal Name
Journal Of Educational And Psychological Researches
مدى تقبل الأطفال لبيئتهم الصفية في الرياض الحكومية والأهلية
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The research aimed at measuring the degree to which the accept their class environment in governmental & civil Kindergartens &  it also aimed at knowing the differences between the dimensions of the measurement & the differences according to the kindergarten & class variables .

The researcher made a measurement for the class environment & it included five dimensions & the answering choices were three ( to a big extent , to some extent and no ) and after making sure that the measurement is usable , the researcher applied it on the sample which consisted of ( 212 )male & female children through the estimated answers of the teacher & the result was that there was an accep

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Publication Date
Tue Aug 15 2023
Journal Name
Al-academy
The shapes of adjacent structures for informing the stage show for children
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This research talked about the importance of adjacent structures for informing the stage show for children. The researcher began from the importance of adjacent structures for informing the show to introduce the various and different proofs, on the level of creativity and artistic shape of the accomplishment over it’s shifts that contribute to formation the show and it's intellectual, artistic, technical and cognitive Marks that contribute in dynamism the interactive show and contact the idea that connect with the design and directional vision for the beauty and cognitive. Lead to the eager operation in attention, sensitive and attractive the child. The research consist of four chapters: The first chapter include methodological framewo

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Publication Date
Tue Jan 15 2019
Journal Name
Arab Science Heritage Journal
الـغـطـاء الـنـباتـي الـطـبـيـعـي في شـرق الـرافـديـن ( أقـالـيـم روافـد دجـلة)
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يكون النبات أحد عناصر النظام البيئي Ecosystem  مع المناخ والتربة والطبوغرافية والموقع وعناصر الحياة الأخرى، والنبات الطبيعي الموجود حالياً, بغض النظر عن مدى تدخل الأنسان, هو في حالة " توازن بيئي" Climax مع

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Publication Date
Sun Nov 01 2020
Journal Name
Iraqi Journal Of Laser
Treatment of facial acne scar using Fractional Er: YAG laser
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Background: Acne is a common disorder experienced by adolescents and persists into adulthood in approximately 12%–14% of cases with psychological and social implications of high gravity. Fractional resurfacing employs a unique mechanism of action that repairs a fraction of skin at a time. The untreated healthy skin remains intact and actually aids the repair process, promoting rapid healing with only a day or two of downtime. Aims: This study, was designed to evaluate the safety and effectiveness of fractional photothermolysis (fractionated Er: YAG laser 2940nm) in treating atrophic acne scars. Methods: 7 females and 3 males with moderate to severe atrophic acne scarring were enrolled in this study that attained private clinic for Derm

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Publication Date
Thu Jul 29 2021
Journal Name
Arab Science Heritage Journal
اللغة ما بين العامية والفصحى في مجلة لغة العرب
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The Arabic language is one of the important magazines that issued in our contemporary history not only on the Iraqi level but according Arabic one as well because it considered

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Publication Date
Tue Jul 01 2008
Journal Name
Journal Of Educational And Psychological Researches
" الصعوبات التي تواجه طلبة الدراسات العليا في أعداد البحوث
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تتزايد الصعوبات التي يعاني منها الطالب بشكل خاص والتدريسي بشكل عام في المرحلة الراهنة وذلك لنقص المصادر والكوادر العلمية الرصينة التي كانت تفخر بها جامعات العراق ولا سيما جامعة بغداد اذ أن الجامعات هي اعلى قيمة في السلم التعليمي وتعد بيئة نقية أوجدها المجتمع للتربية من خلال المناهج الدراسية التي تؤدي بشكل سليم وان الجامعة بوصفها سياقاً اجتماعياً لها أهمية في التشجيع على الإبداع وتعد جيلاً من الشباب للعمل

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Publication Date
Mon Oct 22 2018
Journal Name
Arab Science Heritage Journal
تطور تطور التعليم اليهودي في بغداد خلال العهد الملكي
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That the Jewish minority in Iraq, were considered among the Iraqi people, building.

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Publication Date
Mon Dec 26 2022
Journal Name
Arab Science Heritage Journal
الترادف في التعليق المغني لشمس الحق محمد العظيم آبادي
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Praise be to God, Lord of the Worlds, and prayers and peace be upon our master and beloved Muhammad and all his family and companions. As for what follows: The research presented the synonymous and common verbal expressions mentioned in the book Al-Taliq Al-Mughni on Sunan Al-Daraqutni by the scholar Sheikh Shams Al-Haq Muhammad Al-Azeem Abadi

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