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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
Sun Apr 01 2012
Journal Name
Journal Of Educational And Psychological Researches
تطوير واقع مقرر التطبيقات التدريسية في أقسام كليات التربية جامعة بغداد
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The followers of the reality of the decision application faculty in departments of faculties of education of the University of Baghdad, it is noted that there are many shortcomings, which relate to Path, management, design, and evaluation, Coming from the work of the researcher as a teacher and supervisor, as well as to inform the researcher on many of the studies and literature, luck researcher on the article there are no courses are clear in theory and in practice the decision of the applications teaching, and often puts the teacher education curriculum, which lacks the link between the theoretical and practical, either in relation to its management, there is no office for the management and coordination at the University of Baghdad or

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Publication Date
Thu Apr 07 2022
Journal Name
Journal Of The College Of Basic Education
تاثير تمرينات خاصة في السرعة الادراكية وتعلم بعض المهارات الارضية بالجمناستك
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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of The College Of Languages (jcl)
Le rire amer du point de vue énonciatif dans " la guerre de Troie n' aura pas lieu" de Jean Giraudoux
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Si le rire est censé être le propre de l'homme, il n'en est pas pour autant toujours signe d'intelligence. Qui n'a  jamais eu honte d'avoir ri àune blague idiote ou méchante?

     Il y a plusieurs  façons  de rire , ce qui fait que ce qui est  comique  pour les uns ne l'est pas pour les autres et que le comique réside moins dans l'objet ( situation, blague..) que dans le point de vue et dans l'interprétation que nous en ferons. " Le rire .. contient toutes les mélancolies humaines ([1]) ".

([1] )

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Publication Date
Tue Jan 01 2008
Journal Name
Journal Of Educational And Psychological Researches
البواعث النفسية في رسم لوحة التشبيه - عند شعراء ما قبل الإسلام -
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        مما توصل إليه البحث  :

            إن الدوافع النفسية تنفرد في تجسيد الأحاسيس والمشاعر في نتاج الشاعر , من خلال رؤيته لتلك الحالة , فتسهم في صورة المقارنة في التشبيه , فتبعث في المتلقي حالة التأمل والمقارنة بين الحالتين اللتين تجمع بين مكوناتهما صفة واحدة فتصل إلى حالة التلاحم , ويكون ذلك باعثا لرسم صورة التشبيه ال

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Publication Date
Sun Apr 23 2023
Journal Name
مجلة الجامعة العراقية
قضايا أخلاقية في العل م اخلاقيات العلم والتكنولوجيا وتدريس الكيميا ء
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تهدف هذه المقالة إلى توضيح أخلاقيات العلم وضوابطه التي يجب على من يعمل في هذا المجال أن يكون متحلي بها حتى يحافظ على القيم والأخلاق الفاضلة والموروثة من الآباء والاجداد والنابعة من الصالحين والاخيار لديم ومة الحياة بأفضل وجه وكما يتمناه الكل وكذلك عدم تجاوز الحدود التي تؤدي إلى الأض ا رر بالمجتمع والبيئة . وتوضيح الحدود الغير مسموح بتجاوزها في مجال العلم والتكنولوجيا ومن هذه الأخلاقيات أو الضوابط التي يجب أن

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Publication Date
Sat Oct 01 2022
Journal Name
Al–bahith Al–a'alami
THE IRAQI MEDIA FROM APRIL 2003 TO APRIL 2005
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After the fall of the Iraqi regime in the 9th of April 2003, and after the disintegration of the country, political and party political chaos that had never been witnessed before, has now taken over. In the past 2 years, the American military forces had a primary role in spreading this chaos and disorder by applying a set of wrong measures and policies. This chaos that is still affecting the iraqi people was completely ignored by the USA even 2 years after the occupation, no serious steps have been taken in order to bring back order and security, on the other hand, most of the government institutions and its forces were disintegrated, along with the decision made by Paul Bremer of dismissing all the iraqi journals and the workers of the

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Publication Date
Thu Aug 27 2020
Journal Name
Arab Science Heritage Journal
المقومات السكانية والاقتصادية للمجتمع واثرها في تاريخ بغداد المعاصر 1940-1960م
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       Our research, entitled(Population and economic determinants of society and its impact in the history of contemporary Baghdad 1940-1960), dealt with a number of historical facts and events of the social, demographic and economic

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Publication Date
Thu Mar 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة الأساليب المستخدمة في تحديد عدد المركبات الرئيسية مع التطبيق العملي
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The principal components analysis is used in analyzing many economic and social phenomena; and one of them is related to a large group in our society who are the university instructors. This phenomenon is the delay occurred in getting university instructor to his next scientific title. And as the determination of the principal components number inside the principal components depends on using many methods, we have compared between three of these methods that are: (BARTLETT, SCREE DIAGRAM, JOLLIFFE).

     We concluded that JOLLIFFE method was the best one in analyzing the studying phenomenon data among these three methods, we found the most distinguishing factors effecting on t

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Publication Date
Thu Sep 01 2022
Journal Name
العلوم النفسية
( التفكك الاسري لدى تلامذة الصف السادس الابتدائي في ضوء بعض المتغيرات)
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الملخص: لتحقيق أهداف البحث قامت الباحثتان ببناء مقياس للتفكك الاسري اعتمادا على نظرية (باندورا) وتكون بصورته النهائية من (24) فقرة ، وطبق المقياس على عينة البحث البالغة (150) تلميذ وتلميذة تم اختيارهم بالطريقة العشوائية البسيطة من مجتمع البحث ،وبعد جمع البيانات تم معالجتها باستعمال الوسائل الإحصائية منها الاختبار التائي، وتحليل التباين الرباعي والاختبار الفائي، وتوصل البحث الى النتائج الأتية :ان أفراد عينة ال

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Publication Date
Thu Dec 31 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Measuring the Impact of Commitment to Apply Banking Governance Mechanisms
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This research aims to measure the impact of applying bank governance mechanisms in reducing the financial risks of banks listed on the Palestine Stock Exchange, and to answer research questions and test hypotheses for the study, researchers adopted the descriptive and analytical approach, and data were collected from the annual financial reports of the banks listed on the Palestine Exchange during the period between (2009-2018), as a time series for the purpose of finding, analyzing and measuring the effect between the study variables during this period by (60) views for each of the study variables, using the statistical analysis program views(9) to enter, process and analyze the data. The results of the study proved that there i

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