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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 Feb 03 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Effect of The Mental image Building Dimensions for The Company to Aattract Attention of Iraqi Consumers for local Products: Exploratory Study
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The survey showed sample opinions of officials in the general company for vegetable oils industry, and the statement of the order of the effect of these dimensions depending on the degree of importance, the questionnaire was used as a key tool in collecting data and information of the sample consisted of 30 officials, arithmetic mean, standard deviation, percentages, Spearman correlation coefficient and the global statistical analysis as a statistical methods that based on statistical program (SPSS), The researcher came to several conclusions, most important that there is high agreement by the respondents of the importance of the dimensions of building a mental picture of the company and to attract the consumer's attention, Also research

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Publication Date
Wed Oct 24 2018
Journal Name
Journal Of Planner And Development
الآليات التخطيطية لتوفير خدمات البنى التحتية في قطاع الإسكان (مدينة الكاظمية المقدسة إنموذجاﹰ )- محلة 413،405،407
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Publication Date
Tue Dec 27 2022
Journal Name
Journal Of The College Of Basic Education
فاعلية أنموذج (سكمب المعدل) في الأصالة الرياضية واتجاه طلاب الصف السادس العلمي نحو البرهان الرياضي
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هدف البحث الحالي التعرف على فاعلية انموذج سكمب المعدل في الأصالة الرياضية واتجاه طلاب الصف السادس العلمي نحو البرهان الرياضي ، تَمَّ الاستعانة بالتصميم التجريبي ذي الاختبار البعدي والضبط الجزئي لمجوعتين متكافئتين (تجريبية وضابطة) ، تكونت عينة البحث من (55) طالباً من طلاب الصف السادس العلمي في ثانوية ابن الهيثم للبنين الواقعة في مركز محافظة القادسية ، جرى توزيع طلاب عينة البحث عشوائياً إلى مجموعتين إحداهما تج

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Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
التخطيط التخطيط العمراني والسكاني لمدينة بغداد في عهد الوالي العثماني محمد رشيد الكوزلكي 1852-1857
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I've dealt with my research is marked by ((urban and population planning for the city of Baghdad, during the reign of the Ottoman governor Muhammad Rashid Alkozlki 1852-1857)), a set of facts and incidents historical with the physical and demographic dimension, which passed on the history of the city of Baghdad on the fifth of the nineteenth century the contract during the Ottoman control Iraq, which lasted almost nearly four centuries

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Publication Date
Mon Nov 19 2018
Journal Name
Arab Science Heritage Journal
مصطلح مصطلح (i3-gal2) في ضوء نصوص مسمارية غير منشورة من عصر سلالة أور الثالثة
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The verbal formula // i3-gal2 //is a commonly form in the written Sumerian economic texts, starting from the early dynastic period (2900-2372 BC), ending with the Ur III dynasty (2112-2004 BC).  This formula has appeared either without infixes, or accompanied by infixes like / in-da-gal2/,  corresponded in Akkadian the formula: ibaššu ,which is  means "to found, to Storage ", As to the formula / da / come to indicate "to found with, to storage with--).

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Publication Date
Sat May 02 2026
Journal Name
حوليات اداب عين شمس
דמותו של המאהב הערבי ברומן גדר חיה של דורית רביניאן ורומן יסמין של אלי עמיר מחקר השוואתי
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מחקר זה בוחן את התפתחות הדימוי של ערבים בספרות הישראלית דרך עבודותיהם של אלי עמיר ודורית רביניאן שני סופרים חשובים שסיפוריהם מאתגרים סטריאוטיפים שוררים ומרחיבים את ההבנה התרבותית הניתוח הממוקם במסגרת הספרות המזרחית עוקב אחר האופן שבו דמויות ערביות עוברות מדמויות שוליים לאנשים מורכבים ומעודנים המשקפים שינויים סוציו פוליטיים רחבים יותר על ידי השוואת חקר הזהות והעקירה של עמיר בסביבה היהודית בבגדד לבין

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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
Mon Nov 12 2018
Journal Name
Arab Science Heritage Journal
الحجاج الحِـجاج في الشـعر الأنـدلـسي_ عـصر الطوائـف - (حجاجية الورد والنرجس لأبي بكر بن القوطية* أنموذجاً)
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Argumentation in the era of Andalusia poetry Denominate on the orbital roses and narcissus to Abu Bakr bin Gothic model research deals with the subject of Argumentation and employment in Andalusia Poetry has been studied in two sections display in the first reasons of self- Argumentation included human relationships

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Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
The Requirements of Achieving Sustainable Competitive Advantage under Framework of Constructing Green Strategy for Business Organizations ( perceptual analytical study)
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The aim of this research is to know how business organizations achieve competitive advantage ,and make it sustainable through constructing a green strategy ( friend to environment) which is reflected on sustaining their competitive advantages .The problem of this study is presented through trying to answer many thoughtful questions, the most important of them are: 

1-Can business organizations today make green strategies supporting their competitive advantage?

2-Is there a framework or mechanism could be depended on by business organizations to manage strategic risks of losing their competit

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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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