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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
Wed Sep 25 2019
Journal Name
Journal Of The College Of Education For Women
اثر إستراتيجية شكل البيت الدائري في الأداء التعبيري لدى تلاميذ الصف الخامس الابتدائي
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أجري هذا البحث في العراق/محافظة ديالى، وهدف إلى تعرف أثر إستراتيجية شكل البيت الدائري في الاداء التعبيري لدى تلاميذ الصف الخامس الابتدائي,وبلغت عينة البحث(75) تلميذا بواقع (40) تلميذا في المجموعة التجريبية و(35)تلميذا في المجموعة الضابطة ، وأجرى الباحث بينهما تكافؤا في المتغيرات الآتية (العمر الزمني  محسوبا بالشهور، والتحصيل الدراسي للأبوين ، ودرجات اللغة العربية للعام الدراسي السابق واستعمل الباحث أداة م

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Publication Date
Tue Jul 11 2023
Journal Name
Journal Of Educational And Psychological Researches
Perceptions of Iraqi EFL Pre-service Teachers of Sustainable Development
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Sustainable development (SD) is an improvement that meets present needs but jeopardizes the ability of new populations to do the same. It is vital to acquaint EFL students with the terminology and idiomatic expressions of this discipline. Nowadays, sustainable development and the environment have been prioritized in every aspect of life. Since culture and the teaching of Foreign language English cannot be separated, the English language becomes the mean of communication in health, economics, education, and politics. Thus, integrating sustainable development goals within language learning and teaching is very important. This descriptive quantitative study aims to investigate the perception of EFL pre-service teachers of sustainable develo

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Publication Date
Mon Jul 26 2021
Journal Name
جامعة بغداد/ كلية التربية للعلوم الصرفة - ابن الهيثم
مهارات التفكير الجبري المتضمنة في كتاب الرياضيات للصف الثالث المتوسط وامتلاك الطلبة لها
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Publication Date
Mon Jun 06 2005
Journal Name
مجلة كلية التربية البدينة و علوم الرياضة للبنات
دراسة بعض المتغيرات الوضيفية و النثروبومترية للقلب كانعكاس لتاثير التدريب في الكرة الطائرة
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Publication Date
Sun Jan 01 2017
Journal Name
Journal Of The College Of Languages (jcl)
« L'agressivité de la parole et de l'acte » dans Haute Surveillance et Les Bonnes de Jean Genet
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Sommaire

                      La question de la violence et de l'agressivité  porte une importance remarquable dans l’esprit de Jean Genet qui estime le crime   en le considérant comme beau. Il lui donne une valeur suprême. Il le glorifie avec ses personnages criminels.   Le langage théâtral genétien est violent qui conduit à la fin à l’acte agressif, le crime et la mort. Ce théâtre qui aborde la condition humaine retrace sur la scène le chemin tragique de l’homme moderne.               

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Publication Date
Sun Jan 03 2016
Journal Name
Journal Of Educational And Psychological Researches
إنتاج المعرفة واكتسابها لدى طلبة كليات العلوم التربوية في بعض الجامعات الأردنية الرسمية
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This research attempts to propose production and acquisition of scientific knowledge among the students of educational science faculties in some universities Governmental Jordanian (Yarmouk, Jordan, Muta). In addition to sources of educational gained in some of the Governmental Jordanian universities (Yarmouk, Jordan, Muta), and to propose the necessary socio-cultural dimensions of knowledge acquisition and production, using developmental screening method, which is represented in the study design tool (questionnaire), which consisted of 4 scales, scale: The reality of the acquisition of knowledge / reality of the production of knowledge / social dimensions of knowledge acquisition and production / cultural dimensions of knowl

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Publication Date
Wed Mar 02 2022
Journal Name
Journal Of Educational And Psychological Researches
Awareness Level of the Hidden Curriculum among Field Education Students at College of Education, Ha'il University
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The study aimed to identify the awareness level of hidden curriculum among field education students, College of Education, Hail University. To identify the different awareness level of hidden curriculum among field education students depending on specialization variable, and grade variable in curriculum and instruction course, a descriptive survey method was used. The study sample consisted of (182) students: 78 students in Islamic Culture major, 46 primary major and 58 in physical education. To achieve the study objectives, a hidden curriculum awareness scale was designed included (36) items. The study results showed: the awareness level of hidden curriculum among students of field education, Education College, Hail University, achieved

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Publication Date
Mon Apr 30 2018
Journal Name
مجلة العلوم النفسية
دراسة تحليلية لمحتوى كتاب الفيزياء للصف الرابع العلمي في ضوء مفاهيم التنمية المستدامة
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ان هدف من هذا البحث هو تحليل محتوى كتاب الفيزياء للصف الرابع العلمي و المقرر تدريسه للعام الدراسي (2018-2017). ولتحقيق هذا الهدف، و بعد مراجعة الادب السابق في ضوء مفاهيم التنمية المستدامة، تم تطوير اداة تتضمن مفاهيم التنمية المستدامة وابعادها، حيث تكونت في صورتها النهائية من 51قضية فرعية موزعة بين المفاهيم الثلاثة الساسية: الاجتماعية، والاقتصادية، والبيئية .وبعد التأكد من صدق الاداة وثباتها، تم تحليل محتوى كتاب

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Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
مدخل الجودة ومؤشرات اوسع لتقويم جودة العملية التعليمية دراسة تطبيقية في جامعة بغداد
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المستخلص

يهدف هذا البحث إلى تصميم ومكننة نظام متطور لتقويم جودة العملية التعليمية للجامعات العراقية، باعتماد مدخل الجودة، ومكننة نظام معلومات قادر على توفير البيانات بالخصائص المطلوبة التي يمكن الاستناد إليه في اجراء عملية التقويم على وفق النظام المقترح.

اعتمد البحث على أسلوبيّ دراسة الحالة والدراسة التطبيقية، للوصول إلى النتائج ا

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Publication Date
Mon Jan 02 2017
Journal Name
Journal Of Educational And Psychological Researches
موقف القيادات الجامعية في الأردن من إلغاء وزارة التعليم العالي مدخلا لتنمية المجتمع
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  • The study aimed to identify the position of the university leaders from the proposed abolition of the Ministry of Higher Education in Jordan as un approach for the development of society, the study relied descriptive method survey with the assistance consists of (33) items, and check validity and reliability of the instrument, and was applied to a sample of university leaders, (57) a leading university presidents and their assistants and deans and their assistants, and after processing the data bagful statistical( spss) overall results showed the to arithmetic average of (2.74) and the degree of medium and this means that most respondents moderately support the abolition of the ministry, the most prominent item that makes
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