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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
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
أثر استراتيجية التدريس التبادلي في اكتساب مهارة قراءة الخريطة الجغرافية لدى طالبات الصف الخامس الأدبي
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The aim of this study is to find out the effect of reciprocal teaching   on the fifth literary class pupils in acquiring the skill of geographic map reading. The researcher uses the partial experimental design/pre- post-test for two equivalent control and experimental groups.

   The population of the study is represented by the fifth literary class pupils at a school of the Directorate of Education /Baghdad Karkh second. The sample is selected randomly as section (A) the experimental group and section (C) the control group. The sample total number is (60) pupils, (30) pupils for each group. The two groups are equalized in the following variables: IQ, age and the pupils’ previous geog

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Publication Date
Mon Jun 01 2015
Journal Name
Journal Of The College Of Languages (jcl)
ES’AT NAİB’İN “ZAMANIN ELİ” ADLI DİVANINDA İSİM ÇEKİM EKLERİ (Karşılaştırmalı İnceleme)
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Irak Türk ağızları Azeri Türkçesinin bir uzantısı olarak değerlendirilir.Kerkük Türkçesiyle yazılan edebi ürünler, Irak Türkçesinin tamamını ifade etmek üzere kullanılmaktadır. Zamanın Eli divanı Kerkük Türkçesile yazılan bir eserdir. Bu yüzden bu divanı seçtik ve Irak Türkmen Türkçesi , Osmanlı Türkçesi ve Türkiye Türkçesi dilleri arasında  karşılaştırmalı bir inceleme yaptık.

Bu araştırma, Irak Türkmen şairlerinden birisi  sayılan  Es’at Naib’in  şiirleri üzerinde uygulamalı bir çalışmadanoluşmaktadır. Bu çalışmada adı geçen şairin “Zamanın Eli” Divanından bazışiirlerini önce yeni Türkçeye çevirdik vedaha sonra isim ç

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Publication Date
Mon Jan 02 2017
Journal Name
Journal Of Educational And Psychological Researches
تقويم جودة مهارات التدريس لدى مدرسي الرياضيات في المرحلة الإعدادية الفرع العلمي من وجهة نظرهم
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   Research aims at evaluating the quality of the teaching skills of math teachers in junior high / scientific branch  from their point of view.

The researchers prepared for this purpose a quality of teaching skills standards questionnaire, It consisted of 72 items distributed on four axis, The research sample was 200 teachers The researchers used statistical methods: the arithmetic mean, standard deviation, variance test, test Shiva  , The results showed a statistically significance difference Attributed to the qualification  variable  in the second  axis (Planning for teaching topics) And the absence of statistical difference function,

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Publication Date
Mon Dec 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
إيجاد الحل المقبول (الممكن) والأمثل لأنموذج البرمجة الخطية في ظل عدم تحقق شرطّي الإمكانية والأمثلية
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تعد البرمجة الخطية عاملاً مؤثراً وفعالاً في عملية صنع و إتخاذ القرار عندما تكون الموارد متاحة أو متوفرة لكي تعطي أهدافاً معينة ، وتكمن البرمجة الخطية في حل وتقييم الانشطة أو الفعاليات عند تطبيق إحدى أدواتها وهي الطريقة المبسطة العامة ، التي يكون فيها الحل مقبولاً (ممكناً) ويجب التوصل الى الحل الامثل عندها تسمى بالطريقة المبسطة الاولية أو يكون الحل فيها أمثلاً ويجب التوصل الى الحل الم

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Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
التعايش السلمي في الاسلام بين التنظير والتطبيق عهد الامام علي (عليه السلام) للاشتر النخعي / انموذجا
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     Peaceful coexistence is not seen as a new topic of secretions of modern civilization, a requirement to solve the problems of our era or one of the indications of urgent immediate needs, rather, tolerance is considered basis for building a state. Therefore, we can touch on the principles and basics of tolerance in the Holy Qur’an, the speeches of the Messenger (may God bless him and grant him peace) and his hadiths, and the principle of brotherhood that he established

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Publication Date
Sat Nov 10 2018
Journal Name
Journal Of Planner And Development
(دور الوعي البيئي لدى الأسرة العراقية في التخلص من النفايات الصلبة) (مدينة الرمادي – حي العزيزية)
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Publication Date
Mon Oct 01 2007
Journal Name
Journal Of Educational And Psychological Researches
تقويم طرائق التدريس والتقنيات التربوية والأختبارات التحصيلية لدى أعضاء الهيئة التدريسية في جامعتي بغداد والنهرين
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أن أزدياد أعداد الطلبة في معظم دول العالم ، والتوسع في التعليم العالي ، أدى الى أستيعاب أعداد كبيرة في المؤسسات التعليمية من حملة الشهادات العليا الماجستير خاصة والدكتوراه ، وأن برامج الدراسات العليا وضعت لأعداد باحثين مختصين في مجالات عدة منها التدريس وما يتطلبه من مهارات مختلفة ، فأن قسماً منهم ليست لديه المعرفة النظرية والتطبيق العملي والمهارات اللازمة لأستخدام طرائق التدريس والتقنيات التربوية أث

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Publication Date
Thu Dec 26 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
اتجاهات تطوير أنشطة الرقابة الداخلية لتلبية متطلبات لجنة التدقيق: دراسة تطبيقية في مصرف اشور الدولي
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The audit committee has received considerable attention from international institutions and researchers as a result of financial failures and the collapse of major international companies, especially cases of manipulation and misinformation in the financial statements, due to the role played by one of the mechanisms of control of economic entities to increase disclosure and credibility of information published, In overseeing the preparation of financial reports, following up the internal auditing functions, supporting the external auditor and enhancing his independence, and strengthening the shareholders' confidence in the economic entity. The two researchers prepared the applied side of the research by applying a proposed model based on

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Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
تصـمـيم ومــحـاكاة سلسلة التجـهـيز الالكترونية دراسـة حـالة في الـشـركة الـعـامـة للـصـناعـات الـصـوفية – مـعـمل 1 أيـار
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Supply Chain Management (SCM) attempts to a create a synchronization of the firm’s processes and those of the supplier to match the flow of materials, services, and information with the customer demand. Due to its importance, the SCM has become inevitable to modern companies. Therefore this research work has been conducted to set a theoretical and applied basis to assist the 1 AYAR factory in adopting the Electronic Supply Chain (e-SC).  To accomplish that the searchers applied many tools such as: quantitative and qualitative analysis, process analysis, Visual Basic software, Monte Carlo Simulation to simulation the designed supply chain to compare its performance against the actual performance of the current supply chain

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Assessing Service Quality using Data Envelopment analysis Case study at the Iraqi Middle East Investment Bank
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The use of data envelopment analysis method helps to improve the performance of organizations in order to exploit their resources efficiently in order to improve the service quality. represented study a problem in need of the Iraqi Middle East Investment Bank to assess the performance of bank branches, according to the service quality provided, Thus, the importance of the study is to contribute using a scientific and systematic method by applying  the data envelopment analysis method in assessing the service quality provided by the bank branches, The study focused on achieving the goal of determining the efficiency of the  services quality provided by the bank branches manner which reflect the extent of utilization of a

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