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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 Jul 01 2010
Journal Name
Political Sciences Journal
حل الاشكالية المنهجية في العلوم الانسانية المنهج البنيوي انموذجاً مقترحاً
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حل الاشكالية المنهجية في العلوم الانسانية المنهج البنيوي انموذجاً مقترحاً

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Publication Date
Wed Jun 01 2016
Journal Name
Journal Of The College Of Languages (jcl)
Estudio lexicográfico sobre la Terminología de la Planta “Maíz” en Andalucía
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Andalucía, dentro del mapa lingüístico español, es una región con muchas variaciones dialécticas. En muchos casos contiene una gran variedad de términos propios de la zona, ya que en esta misma zona se pueden observar muchas subdivisiones dialectales.

En este trabajo, hemos seguido dos tipos de fuentes:

- Directa: Se trata de conseguir la información por medio de cuestionarios distribuidos a informantes de edades y localidades diferentes.

 - Indirecta: Consultando libros para conseguir información y datos básicos del tema, e información sobre las voces y nombres dialectales en la geografía estudiada.

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Publication Date
Thu Nov 12 2020
Journal Name
Arab Science Heritage Journal
الجوانب الادارية والقضائية في كتاب المسند للإمام ابي يعلى الموصلي
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The Studying of  historian aspects in Al-Hadieth books  , such as " Al-Musnad  Book    " subjected to  Al-Imam Abi Yalaa Al-mousily" ,has great importance in the field of Islamic history , in which Al- Al-Imam Abi Yalaa Al-mousily  has presented valued information that  have significant impact on the understanding of history, Have a significant impact on the understanding of Islamic history

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Publication Date
Sat Sep 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
استخدام برمجة (DeNovo) لتطوير شبكة المياه في استراتيجيات القرار المتعدد
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The object of this study is to establish a global model to use of DeNovo programming the strategies of multi-Decision making process in the city of Baghdad.

Thus, we have chosen an important and an effective subject in the life of the citizen due to the importance of this subject in the Iraqi citizen of luck of water and for many reasons.

In this thesis, we have tackled the establishment of a global model to be able to reach solution or an alternative model a money the available alternative.

        The alternative proposed here utilizes the application of the (DeNovo) programming approach suggested by (1982) in solving t

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Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
The use of analytical procedures to detect Earning Management Practices
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            That analytical procedures are of analytical tools important because it gives assurance to the auditor-free financial statements of the economic units replace the audit of cases offraud and errors and distortions, and thereby to increase the effectiveness of the audit process and confirm the possibility oftrust and reliance on the financial statements that Adfgaha auditor.
Inspite of identify evidence of proof necessary to enhance the auditor's opinion the results reached in the audit p

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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
Sun Oct 02 2016
Journal Name
Journal Of Educational And Psychological Researches
IQ TEST STANDARDIZATION OF MARTEN LOTHER JOHAN WITH CHILDREEN OF THE SIX YEAR
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This study aimed to IQ test standardization of Marten Lother Johan which used with childreen of the one stage at primary schools who aged (6) 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 follow

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Publication Date
Wed Feb 10 2016
Journal Name
ألمؤتمر الدولي العلمي الخامس للاحصائيين العرب/ القاهرة
Proposition of Modified Genetic Algorithm to Estimate Additive Model by using Simulation
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Often phenomena suffer from disturbances in their data as well as the difficulty of formulation, especially with a lack of clarity in the response, or the large number of essential differences plaguing the experimental units that have been taking this data from them. Thus emerged the need to include an estimation method implicit rating of these experimental units using the method of discrimination or create blocks for each item of these experimental units in the hope of controlling their responses and make it more homogeneous. Because of the development in the field of computers and taking the principle of the integration of sciences it has been found that modern algorithms used in the field of Computer Science genetic algorithm or ant colo

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Publication Date
Mon Dec 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
السياسة النقدية في العراق بعد 9/4/2003 (الواقع والطموح)
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لا يستطيع كل كائن حي أو كيان اجتماعي أداء دوره الذي يفترض أن يقوم به ما لم يمتلك الوسائل الكافية والضرورية لأداء ذلك الدور قال سبحانه وتعالى ((قال ربنا الذي أعطى كل شيء خلقه ثم هدى طه 50)).

والنشاط الاقتصادي كجزء من الكيان الكلي للمجتمع لا يختلف عن هذه القاعدة، إذ عندما يراد من النظام الاقتصادي أداء دور فاعل فلا غنى له عن الوسائل التي تمكنه من أداء دوره المنشود. للنظام الاقتصادي مجمو

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Publication Date
Mon Dec 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
دور مراقب الحسابات في ظل تكنولوجيا المعلومات المعقدة ومخاطر التدقيق
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بدأت الشركات تخطو خطوات متسارعة  باستخدام أنظمة تكنولوجيا المعلومات في عملياتها المالية وباعتماد قليل على الورق والذي يتم الاحتفاظ بالنسخ الأصلية منه تعزيزا للإجراءات التي تمت معالجتها الكترونيا. إن ممارسة الشركات وبشكل متزايد الأسلوب الواقعي (Virtualization) في علاقاتها مع الموردين والمستهلكين والشركاء أدى للحاجة المتزايدة للثقة والتأكيد على مثل هذه العلاقات مما يولد ضغطا  كبيرا ع

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