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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
Thu Jun 01 2006
Journal Name
Journal Of The College Of Languages (jcl)
L'image de l'Arabe et l'attitude d'Albert Camus envers la question algérienne dans sa nouvelle "L'Hôte" de son recueil "L'Exil et le Royaume" : Une étude analytique
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Parmi les oeuvres d'Albert Camus, qui s'éloignent un peu de sa
tendance générale qui traite les thèmes de l'absurde ,du néant et de la
question de la mort , on trouve son recueil "l'Exil et le Royaume" 1957
qui contient six nouvelles qui sont d'une invention moins épouvantable
(le Renégat , la Femme adultère , les Muets , le Pierre qui pousse , l'Hôte
et Jonas). Ces nouvelles , à l'exception du "Renégat" , ne provoquent pas
les questions philosophiques et dialectiques qui dominent la plupart des
oeuvres d'Albert Camus , Mais ces nouvelles traitent tout simplement la
question d'homme exilé dans son existence et sa recherche perpétuelle
de son royaume.

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
تطبيقات منحنى لورنز ودليل التركيز في كشف تغايرات مساحات وتكرارات وحدات الخارطة لمشاريع من وسط السهل الرسوبي العراقي
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0

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Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
Field Study of Novel Storage Tank of Solar Water Heating System
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In this paper thermo-hydrodynamic characteristics were investigated experimentally for a new type shell-helical coiled tube heat exchanger used as a storage tank of closed loop solar water heater system. Triple concentric helical coils were made of copper tubes of (12.5mm OD and 10mm ID) with coils diameter of (207, 152.2, 97mm) for outer, middle and inner coils respectively. The experiments were carried out during a clear sky days of (March and April 2012). The parameters studied in this work are: history of average temperature of shell side of the storage tank, collector heat gain, heat rejected from coils to shell side of the storage tank, collector efficiency, thermal effectiveness of the heat exchanger (storage tank), and pressure d

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Publication Date
Wed Apr 25 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Finite Element Method With Linear Rectangular Element for Solving Nanoscale InAs⁄GaAs Quantum Ring Structures
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        This paper is concerned with the solution of the nanoscale structures consisting of the   with an effective mass envelope function theory, the electronic states of the  quantum ring are studied.  In calculations, the effects due to the different effective masses of electrons in and out the rings are included. The energy levels of the electron are calculated in the different shapes of rings, i.e., that the inner radius of rings sensitively change the electronic states. The energy levels of the electron are not sensitively dependent on the outer radius for large rings. The structures of  quantum rings are studied by the one electronic band Hamiltonian effective mass approximati

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Publication Date
Tue Feb 02 2021
Journal Name
جامعة واسط مجلة كلية التربية
استعمال الانموذج اللوجستي ثنائي المعلم في بناء وتدريج مقياس الشخصية الافتراضية المتعدد الابعاد لطلبة الجامعة وفقا لنظرية الاستجابة للفقرة
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تهدف الدراسة الحالية الى استعمال الانموذج اللوجستي ثنائي المعلم في تدريج مقياس الشخصية الافتراضية المتعدد الابعاد لطلبة الجامعة وفقا لنظرية الاستجابة للفقرة، والخروج بتعميم لنتائج البحث والوقوف على الاجراءات العلمية المناسبة وتوفير تطبيق عملي علمي صحيح لاعتمادها من قبل الباحثين. وقد اتبعث الباحثة الاسلوب العلمي من خطوات واجراءات في عملية بناء المقياس حيث حدت ابعاد الشخصية الافتراضية المتمثلة بسبع ابعا

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Publication Date
Wed Mar 12 2025
Journal Name
Kufa Journal Physical Education Sciences
اثر تدريبات بأسلوب التدريب الدائري لبناء التحمل في تطوير بعض القدرات الحركية لأشبال لكرة القدم بأعمار (13- 15) سنة
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اهمية البحث هي مرحلة نمو وبناء اجهزة الجسم للاعبين الاشبال واعداد تدريبات بأسلوب التدريب الدائري لبناء التحمل لتطوير بعض القدرات الحركية والمهارية لدى اللاعبين الاشبال بكرة القدم , حيث لاحظت الباحثة ضعف في مستوى الاداء الحركي ارتأت اعداداً بدنيا ومهارياً منذ مرحلة البناء الأولى للاعب الفئات العمرية , واستخدم الباحث المنهج التجريبي بالاختبار القبلي والبعدي للمجموعتين التجريبية والضابطة لملائمته لطبيعة ال

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Publication Date
Sun Jul 06 2014
Journal Name
Journal Of Educational And Psychological Researches
أصول التربية : تضارب المحتوى وإشكالية الإعداد دراسة نقدية لكتب ومقررات أصول التربية في الجامعات العربية ووضع تصور منهاجي بديل
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Research questions  start from the fact that what the Arab origins of education  indicted . First question are :

- To what extent the subject of assets acquired a specific meaning in the Arabic books and educational subjects ? Is these selections are reflected on the classification of assets and their types ?
- What’s the nature of the content ? .Is there a consistency between the meaning and content ?

- What entrances handling and curriculum approach and tactics are in those books ?

- Is the assets subject introduced within  the grade  best suited ?

         &nb

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Publication Date
Sun Dec 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
The impact of re-engineering to achieve effective performance level of Ministry of electricity operations/an applied study of process reengineering clean solar cells
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 The study is dealing with an application reengineering process clean solar cells in the Ministry of electricity,  as aimed at the possibility of the applicability and impact of re-engineering to achieve the level of performance of the Ministry's operations, with the application of the cleaning process  solar cells, developed, improved and found a correlation, statistically significant effect between variable re-engineering and performance as well as the application of process reengineering clean solar cells:1- Before the re-engineering process the total time for cleaning up and solar cell 20 minutes and number of columns performed per day 24 columns and total  columns750 which were completed per month that re

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Publication Date
Thu Dec 31 2020
Journal Name
College Of Islamic Sciences
نماذج من التمازج في قصص الأنبياء بين التشريعات السماوية الثلاث : الإسلامية واليهودية والنصرانية: التشريعات السماوية الثلاث: الاسلامية واليهودية والنصرانية
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   يهدف هذا البحث إلى تأصيل الإستدلال بالقاعدة العقائدية، وبيان ضوابطه، وإبراز نماذج من أهم تطبيقاته المعاصرة، وقد أعتمد مناهج من أهمها المنهج الإستقرائي والمنهج المقارن ، وتناول البحث التعريف لقصص النبوة فى الأديان السماوية ، وعرض بعض الدراسات السابقة التى تناولت نفس الموضوع ، ثم تطرق البحث لذكر نماذج من قصص الأنبياء من الديانات السماوية الثلاث ، وتوصل البحث الى أن الأديان السماوية رغم بعض الإختلاف

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Publication Date
Thu Sep 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
الحوكمة المؤسسية المصرفية ومدى توافر دعائمها للوقاية من ألأزمات المالية في المصارف العراقية الخاصة المقيدة بسوق العراق للأوراق المالية
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Growing interest in the subject of corporate governance after the repercussions of financial collapses of some of the leaders of American companies and European, and the consequent crisis of confidence in global financial lists of companies due to weak accounting disclosure and transparency, was quick from many countries and international organizations to adopt the concept in an attempt to improve the situation of companies and promote transparency and prevent further financial crises in the future. Based on this background, the present study aims to shed light on the concept of exercising the powers of governance that has become invitations for adoption in Iraq of great importance, given the increasing role of corporations both restrict

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