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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
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
Status Judgment : New Insight into the Promoting Process of Entrepreneurial Behavior
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The present study aims to explore determinants of entrepreneurial behavior from perspective of social theory. It is based on model notions of (Tyler & Blader, 2003) which have focused on studying role of positively personal and social identity in motivating employees to practicing desired behavior which serves the organization in which they work. Based on these notions and previous literature, study model were built. This model explains the relationship between status judgments (perceived internal respect and perceived external prestige)  and entrepreneurial behavior. It includes three main hypotheses. The first and second hypothesis are concerning the relationship between status judgmen

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Publication Date
Sun Apr 01 2012
Journal Name
Journal Of Educational And Psychological Researches
حقوق الطفل في ظل الأزمات المجتمعية /الطفل العراقي انموذجا
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Rights of child in the community crisis Iraqi child model The study aimed to identify the types of violation against children in the Iraqi crisis as well as to develop community coping mechanisms to these violations and promote the rights of the child health psychological , social and legal . the first chapter discusses the research problem and its importance and purpose of the research problem and its importance and purpose of the research and the most important terms in the A- Rights of the child ,B- crisis , chapter 2 rights of the child ensure the historical roots , of children’s rights in the holy quran and the sunnah, and legal rights through the twentieth century and the beginnings of century xx, the se through the twentieth cen

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Publication Date
Sun Oct 02 2016
Journal Name
Journal Of Educational And Psychological Researches
القيادة الاستراتيجية المحددة لفاعلية الادارة العليا في جامعة النهرين
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Advantage of the science of management for a lot of other sciences vitality and openness to the rest of the science and knowledge of the various branches fields, and at the same time, overlapping and intermingling majora between the various branches of administration and specialties, and based on this fact, the idea of this research to come out of one of the important topics with two topics of vital in the field of strategic management, namely patterns Strategic Command, and the effectiveness of senior management teams. I've seen the science of management, particularly in the field of strategic management, large shifts and changes, especially in the last two decades, as the RPR Strategic Management rich field of research and the emergenc

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Publication Date
Wed Dec 20 2023
Journal Name
Arab Science Heritage Journal
التحليل الداللي للكلمات المستبدلة في سورتي المؤمنون و النور
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The words in the Holy Qur’an are distinguished by the
accuracy of expression, their elegance, the lightness of their
performance, the harmony of their timbre, as well as the ease of
their pronunciation. We find the coarse words in which the
movement of sounds and the hesitation of the soul are mixed, as
it was distinguished by the abundance of its words indicating the
same meaning without a phenomenon that the reader or the
listener notices

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Publication Date
Wed Oct 21 2026
Journal Name
Political Studies And Strategic
تطور تكنولوجيا الطائرات بدون طيار في ظل الحروب المستقبلية
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The development of drone technology in state of future warsDrones have recently imposed themselves as an effective multi-tasking weapon. States and armed groups have sought to possess them, due to their importance in delivering painful blows to the enemy at a low cost. This technology has played a prominent and varied role in many wars and stimulated countries to manufacture or obtain it

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Publication Date
Sat Jun 01 2024
Journal Name
مجلة العلوم
الذكاء الاصطناعي والوجود الإنساني: قراءة فكرية في الأبعاد السياسية
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يُعد الذكاء الاصطناعي من العلوم الحديثة التي ارتبطت بالإنسان منذ العقود الخمسة الماضية، وأصبحت السياسة الرقمية جزءاً لا يتجزأ من المجتمع لكونها تُستعمل في أغلب مجالات حياة الإنسان. وهذا ما شجع صانعي السياسات التكنولوجية الجديدة في التفكير بكيفية توظيفه لخدمة مصالحهم العليا السياسية والاقتصادية، بغض النظر عن بذل الجهود للتفكير في تنظيمهم للذكاء الاصطناعي التوليدي، ووضع قيود تراعي التشريعات الدينية، وقوا

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Publication Date
Sun Jan 01 2006
Journal Name
Journal Of Educational And Psychological Researches
اثر لعبة كرة القلب في خفض غضب أطفال الروضة
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مشكلة البحث واهميته :

            يعد الغضب من المظاهر الانفعالية الشائعة في مرحلة الطفولة المبكرة وذلك بسبب كثرة المواقف المثيرة لغضب الطفل في هذه المرحلة ، كما ان الطفل في هذه المرحلة سرعان ما يكتفي في كثير من الاحيان بان غضبه وبكائه طريقة سهلة للوصول الى ما يريد . ويعد المختصون في هذا المجال ، بان نوبات غضب الاطفال ، هي شيء عام طبيعي عند جميع الاطفال ، لكن عندما تكون نوبات عنيفة

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Publication Date
Mon Sep 30 2024
Journal Name
مجلة نسق
بعض اللفظات في صور القران الكريم لفظة اكل انموذجا
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ان الداسات القرانية تعد من الدراسات المتعلقة في اللغة العربية لانها تتعلق بدراسة جانب من جوانب اعجاز القرأن الكريم لذلك قمت بدراسة جانب من جوانب اعجاز القران الا وهي لفظة اكل

Publication Date
Thu Dec 13 2018
Journal Name
Arab Science Heritage Journal
ال أل العاقولي ودورهم العلمي في الحضارة العربية الإسلامية
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The research includes a bout IL- IQulle , and their role in scientific of the Islamic – Arabic civilization , for Dr. Khlood M.Namma the proff in the collage of education for woman , Baghdad university , History department .

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Publication Date
Mon Sep 30 2024
Journal Name
مجلة نسق
الحِراك الشعبي والمُعـارَضة الوطنيَّة في الخليج العربي (1918 1968)
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شَهِدَت منطقة الخليج العربي والسَّاحِل العُماني تصاعد مُستوى الحِراك الشعبي، والمُطالبات بتحقيق الاِستقلال التام، وإنهاء الاِلتِزامات والاِرتِباطات الدولـيَّة سواء كانت في إطار الحِماية أو الاِستِشارة أو الصِّداقة، وأصبحت واجِهات ملحوظة من قِبل الفِئات المُـثـقَّـفة في بدايات العقد الثاني من القرن العشرين، وعبَّرت فيها القِوى الوطنيَّة عن حاجاتها في إجراء عملـيَّات التغيير والتحوّل الاِجتِماعي وعلى

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