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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
Mon Jan 07 2013
Journal Name
Journal Of Educational And Psychological Researches
التماثل والاختلاف في المعتقد المذهبي للوالدين وأثره في تنمية الاتجاه التعصبي المذهبي لابنائهم
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This study aims at measuring the sectarian prejudice attitude with sample of college student and secondary school students. It also aims at detecting the impact of similarities and differences of the sectarian belief with the parents on the development of sectarian prejudice with their parents according the following variables (gender,grade,achievement of the parents).

 The study restricted by a sample consists of (Baghdad,Al-mustansiriya,and Al-Qadisiyah) students and the fourth grade students (males and female). To achieve the goal of this study , the researcher built atoll to measure the sectarian prejudice attitude after verifying its psychometric characteristics , after analyzin

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Publication Date
Fri Mar 21 2025
Journal Name
مجلة اكليل
إسهام تطبيقات التكنولوجيا الرقمية في تطوير الكفاءات النحوية لطلبة اللغة الإسبانية في العراق.
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إسهام تطبيقات التكنولوجيا الرقمية في تطوير الكفاءات النحوية لطلبة اللغة الإسبانية في العراق.

Publication Date
Wed Nov 14 2018
Journal Name
Arab Science Heritage Journal
المهن المهن الحرة عند البخاري في كتابه التاريخ الكبير دراسة في اهميتها الاقتصادية
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The importance of the jurist concentrated on Abu-Abdullah Mohammad Bin Ismael Al- Bukhary who wrote his famous writing (the great history) according to his Modern approach.  His style was clearly aimed to record historical events helped narrators reported novel especially through deep reading to be as a sign of special different style from curriculum historians and their ways. It was an approach like an affect charm to the reader and transmitted to a state of grandeur and pride.  

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Publication Date
Mon Jul 22 2019
Journal Name
Arab Science Heritage Journal
المقابر القديمة في بغداد ومدى الإنتفاع منيا في التخطيط العم ا رني لممدينة
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تعدّ المقابر من المرافق القديمة في المدينة بوصفها تمثل ذاكرة التاريخية لاحتوائها
من أضرحة مشاهير أهل الاصلاح ورجال العلم والفن السياسة. 

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Publication Date
Sun May 27 2012
Journal Name
مجلة دراسات محاسبية ومالية
إنموذج مقترح للحكمانية في المنظمات العامة بالتطبيق في وزارة التعليم العالي والبحث العلمي
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تعد الحوكمة من المداخل التي نالت اهتمام العديد من الباحثين والدارسين في مجال الإدارة والسياسة بوصفها إحدى الفلسفات السائدة والمرغوبة في الفترة الحالية , وأصبح ينظر إليها دواء لجميع الامراض التي تعاني منها الأجهزة الإدارية عموماً بالأخص العامة منها . وقد ارتبط هذا المفهوم بمفاهيم إعادة التنظيم Reforme والاصلاح الإداري المجه لتحسين كفاءة وفاعلية أداء تلك الاجهزة وبما ينعكس على مجمل السمات والمميزات التي تتعلق ب

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Publication Date
Sun Jul 07 2013
Journal Name
Journal Of Educational And Psychological Researches
الكفاءة النوعية لطلبة الدراسات العليا في التخصصات التربوية والنفسية في كليات مدينة بغداد
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This thesis aims at identifying:

  1. The level of qualitative efficiency of higher studies students in educational and psychological fields in the colleges of education Baghdad according to the perspectives of both teachers and students.
  2. The statistical differences in levels of qualitative efficiency of higher studies students in educational and psychological fields in the colleges of education in  Baghdad Collegeteacher's viewpoints with reference to the two variables of the scientific title and gender.
  3. The statistical differences in levels of qualitative efficiency of higher  studies students in the educational and psychological fields

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
ستراتيجية دعم وتطوير الصناعات الصغيرة في ضوء تقويم فاعلية مبادرات القروض في العراق
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أفرزت الظروف الاقتصادية والاجتماعية التي عانى منها الاقتصاد العراقي العديد من الاثار السلبية وتكريس بيئة من شانها التشجيع على اقامة مشاريع صناعية وخدمية لا تتناسب وتغيرات السوق وتعتمد على آلات ومعدات بسيطة وتشتمل أعمال حرفية يدوية الصنع وبائعي التجزئة ومختلف انواع الورش والمصانع والمعامل غير المرخص لها وغير المجازة قانونا، حيث أنتشار المشروعات بشكل عشوائي غير م

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Publication Date
Wed Jun 22 2022
Journal Name
Arab Science Heritage Journal
حقوق المرأة في البيعة لرسول الله () في كتاب المحبر للحبيب البغدادي (ت 245هـ)
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The research deals with one of the rights of women, which Islam granted them, and the pledge of allegiance to women, despite its simple part, represents an important and basic feature of the uniqueness that distinguishes the Islamic religion from all the heavenly religions

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Publication Date
Mon Sep 25 2023
Journal Name
Arab Science Heritage Journal
الامام الجويني و دوره في ازدهار الحياة العلمية في مدينة نيسابور ((ت478هـ/1085م))
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The city of Nishapur is one of the cities that had a prominent position and a clear impact on the flourishing of the scientific movement, and this position that it enjoyed was achieved because of the scholars who were incubating them. Who had a great role in the flourishing of scientific life through his scientific activity, as he worked as a teacher for thirty years in its regular school, in addition to his work in rhetoric, preaching and scientific circles, in addition to his many books in various sciences, as he did not specialize in one science only, but rather collected all the sciences of his time and excelled in them. He enriched the Arab and Islamic library with it.

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Publication Date
Sun Mar 01 2009
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
استخدام محاسبة التكاليف في أحتساب تكاليف المؤسسات التعليمية: دراسة تطبيقية في جامعة بغداد
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The institutions of higher education and scientific research are the strategic institutions in the field of investing the human resources.

 

Expenditure on such institutions is considered a long – term investment. Thus, the financial balancing in such institutions is not a traditional one.

These institutions are not for profit organizations.

Accordingly, they need to have accounting data that are calculated on an agreed upon cost basis due to the continuous growth in the expenditure on the services rendered by these institutions. These calls for the availability of tools that help rationalize the expenditure.

Cost Accounting system is capable of providing the useful data for such purposes an

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