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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 Dec 02 2018
Journal Name
Arab Science Heritage Journal
المضامين الاخلاقية والقيمية في فلسفة التربيةالمضامين
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         The moral implications and value in the philosophy of education are one of the most important topics that should be well worth seeking out, especially in our time because of its great importance in the upbringing of the emerging formation, guidance and evaluation within the system or graded him the values ​​of the society in which they live.

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Publication Date
Mon Nov 12 2018
Journal Name
Arab Science Heritage Journal
حسن حسن التخــلّص في اللغة والعمارة
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This research is an attempt to concern with important subject in Arabic language and criticism . Its conception concern with poet’s ability on transmitting from one subject to another in the same poem without effect on the reader or listener in order not to effect on reader or listener through reading poetry this concern had been taken by many critics and rhetorical which lead to architecture design those the

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Publication Date
Wed Sep 29 2021
Journal Name
College Of Islamic Sciences
Factors affecting the upbringing of good children Lect
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Raising children occupies a prominent place in Islam as a step paving the way for the success of reform projects on the level of diverse human life, and for this reason the recommendation for education was mentioned in the mission entrusted to the Prophet (PBUH), the Almighty said:

(( هُوَ الَّذِي بَعَثَ فِي الْأُمِّيِّينَ رَسُولًا مِّنْهُمْ يَتْلُو عَلَيْهِمْ آيَاتِهِ وَيُزَكِّيهِمْ وَيُعَلِّمُهُمُ الْكِتَابَ وَالْحِكْمَةَ وَإِن كَانُوا مِن قَبْلُ لَفِي ضَلَالٍ مُّبِينٍ))  Jumaa verse /38

The topic of the research that is in your hands deals with the

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Publication Date
Tue Apr 01 2008
Journal Name
Al-academy
البناء اللحني والايقاعي في المقام العراقي
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عرف العراق بتعدد ألوانه الغنائية ، المختلفة حيث نلاحظ من خلال الاختلاف والتنوع ألوانا شتى من هذا الفن في الشمال أو الوسط أو الجنوب، ولكنها في الواقع تنبع في أصل واحد إلا وهو المقام العراقي .وقد وردت في المصادر الموسيقية إشارة إلى قالب موسيقي غنائي تحت اسم المقام في كل في تركيا، إيران، اذربايجان وغيرها، ولكن تسمية المقام في العراق له دلالة أخرى على قالب خاص اشتهر في مدينة بغداد بالذات وينسب إلى فت
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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
المرأة في رسوم جواد سلیم وبیكاسو
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There is a fact we have to admit here, first, that is art innovation, since
its early beginnings, is mostly a male product, and causing to stir interest and
attention, if it was a female one. Psychiatrist and sociologists could give us a
convincing answer or a logical explanation for that. What is really important
here is how the male artist could review his vision to woman, what was the
impact of all these ideas and desires towards each other in their artistic
products? Did he reflect the real role played by the woman in pushing the
artist towards specific ways? Did it related to the struggle for immortality? In
searching for motherhood and life eternity and the partner to find the way to
life. We, often, find

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Publication Date
Fri Nov 15 2024
Journal Name
مجلة الاستاذ للعوم الانسانية والاجتماعية
القراءات القرآنية في مدونات العلوم الاخرى
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Publication Date
Sun Jan 01 2006
Journal Name
Journal Of Educational And Psychological Researches
دور الأسرة في ظاهرة جنوح الأحداث
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تعد الاسرة إحدى الوحدات الاجتماعية التي تهيئ الجيل المتطلع للحياة وهم الاطفال، وهي المهد الطبيعي للطبقة البشرية التي تباشر وتواجه اثراً هاماً تكوين الشخصية والسلوك الاجتماعي والخلقي ، وهي نقطة الوصول والتفاعل بين البيولوجي والاجتماعي وعنها ينشأ التفاعل النفساني ، وشبكة العلاقات الاسرية والعلاقات الخارجية المجتمعة . ومن خلال معاييرها وقيمها ينشأ السلوك سوياً كان ام مرضياً ( جانحاً ) ، ومشكلة جنوح الا

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Publication Date
Sun Mar 26 2023
Journal Name
Arab Science Heritage Journal
تمظهرات الإيهام في العصر الإسلامي والأموي
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In this research, trying to highlight the reasons for the illusion, and do not want to repeat what the previous scholars and researchers from the ancients and modernists said, but to continue from where they ended, as the blogging has undergone several images that influenced the nature of the narrations, and their proximity to the truth according to the whims of the authority, or the narrator's whims and inclinations and any destination. Here we don't mean bees and plagiarism... It goes beyond the fact that traffic is made to the whims of those who write or write to it, or in it a little bit of truth and then be framed, to add exaggeration and exaggeration to it.

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Publication Date
Mon Sep 20 2021
Journal Name
Key Engineering Materials
Effect of Partial Substitution of Sr by Ba on the Structural Properties of Tl<sub>0.8</sub>Ni<sub>0.2</sub>Sr<sub>2-x</sub>Br<sub>x</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>9-δ</sub> System
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In this manuscript, the effect of substituting strontium with barium on the structural properties of Tl0.8Ni0.2Sr2-xBrxCa2Cu3O9-δcompound with x= 0, 0.2, 0.4, have been studied. Samples were prepared using solid state reaction technique, suitable oxides alternatives of Pb2O3, CaO, BaO and CuO with 99.99% purity as raw materials and then mixed. They were prepared in the form of discs with a diameter of 1.5 cm and a thickness of (0.2-0.3) cm under pressures 7 tons / cm2, and the samples were sintered at a constant temperature o

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Publication Date
Mon Jun 15 2015
Journal Name
Translation Studies
Difficulties Encountered By EFL Iraqi Undergraduate Students in Handling Subordinate Clauses الصعوبات التي يواجهها طلبة المرحلة الجامعية العراقيون من دارسي اللغة الإنكليزية كلغة أجنبية في استخدام الجمل التابعة
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this paper consists of three sections, Section one deals with the most important difficulties and characteristics of English subordinate clauses whereas section two tackles the difficulties faced by the Iraqi EFL students at the third year in the Department of English, College of languages, University of Baghdad in recognizing and producing the subordinate clauses submitting them to a test consisting of two questions (recognition and production). Finally, some pedagogical recommendation of the findings can be found in section four.