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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 Feb 01 2006
Journal Name
Political Sciences Journal
ملامح من فكرة القانون الطبيعي في حضارة العراق القديم
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ملامح من فكرة القانون الطبيعي في حضارة العراق القديم

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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of The College Of Languages (jcl)
رواية بوهيميا الخراب دراسة تأويلية في جدلية النص والزمن
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Bohemia AL-Kharab for Salah Salah Which contain 477Paper deal With History of Nathion This Novel Has a different styl from another IraQis Novels, this Novel has no conversation this is the basic reason Which hav this research .

The novel have 3 versions , the first one deal with explain the text in different ways , the second contains the realation ship between the text and the reader .

Which appear very clear in novel from up to down , whil the third one and the last explaine

The hermonologiq

The time bylose the relation in the novel.

The last thing is the conclusion which has the simple things  conclude by the researcher from several readings  to the novel

 

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Publication Date
Sun Nov 01 2020
Journal Name
Iraqi Journal Of Laser
Treatment of facial acne scar using Fractional Er: YAG laser
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Background: Acne is a common disorder experienced by adolescents and persists into adulthood in approximately 12%–14% of cases with psychological and social implications of high gravity. Fractional resurfacing employs a unique mechanism of action that repairs a fraction of skin at a time. The untreated healthy skin remains intact and actually aids the repair process, promoting rapid healing with only a day or two of downtime. Aims: This study, was designed to evaluate the safety and effectiveness of fractional photothermolysis (fractionated Er: YAG laser 2940nm) in treating atrophic acne scars. Methods: 7 females and 3 males with moderate to severe atrophic acne scarring were enrolled in this study that attained private clinic for Derm

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Publication Date
Tue Jan 15 2019
Journal Name
Arab Science Heritage Journal
الـغـطـاء الـنـباتـي الـطـبـيـعـي في شـرق الـرافـديـن ( أقـالـيـم روافـد دجـلة)
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يكون النبات أحد عناصر النظام البيئي Ecosystem  مع المناخ والتربة والطبوغرافية والموقع وعناصر الحياة الأخرى، والنبات الطبيعي الموجود حالياً, بغض النظر عن مدى تدخل الأنسان, هو في حالة " توازن بيئي" Climax مع

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Publication Date
Sun Jun 01 2008
Journal Name
Journal Of The College Of Languages (jcl)
The Iraqi Learners' Production Of rp Clipped Vowel
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Within connected speech, RP speakers tend to shorten stressed long vowels end diphthongs in pre. Forties consonants in the same syllable on the basis of complementary Distribution, i.e., the phonological environment decides the influence of the forties plosives and fricatives, as far as they are in find position preceded by stressed long vowels and diphthongs, or particular voiced consonants plus vowels. The Iraqi learners, then, face.

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Publication Date
Wed Nov 14 2018
Journal Name
Arab Science Heritage Journal
الامام الإمام الطرطوشي (520هـ) وآراؤه الفقهية في الأحوال الشخصية
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This research deals with the ideas of Imam Muhammad bin Al-Waleed bin Khalaf bin Sulaiman bin Ayyub , Al -Qurashi, The Moroccan, The  Andalusian, Al-Maliki. He was  known as Abu Bakr Al-Tartoushey , where thesis deals  with the details of his personal life and as well as his scientific path  as well as  his works, and also covered the views of jurisprudence in the personal status and especially on the subject of divorce and inheritance,

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Publication Date
Sat Jun 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Using Some Robust Methods For Handling the Problem of Multicollinearity
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The multiple linear regression model is an important regression model that has attracted many researchers in different fields including applied mathematics, business, medicine, and social sciences , Linear regression models involving a large number of independent variables are poorly performing due to large variation and lead to inaccurate conclusions , One of the most important problems in the regression analysis is the multicollinearity Problem, which is considered one of the most important problems that has become known to many researchers  , As well as their effects on the multiple linear regression model, In addition to multicollinearity, the problem of outliers in data is one of the difficulties in constructing the reg

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Publication Date
Wed Sep 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
مكافحة ظاهرة الفساد في إطار تكامل المحتويين الإداري والاستراتيجي
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ينقسم الاتجاه الأساسي الذي يجري مناقشته في هذه الورقة إلى مستويين: الأول يركز على تحديد مضمون العلاقة بين الشفافية والفساد، فضلا عن توضيح الدور الذي يمكن أن تؤديه أخلاقيات الأعمال، لتثار التساؤلات هي: هل أن الشفافية والفساد متغيرين مرتبطين معا؟ وهل تؤثر الشفافية في الفساد؟ وهل أن وجود الشفافية كفيل بإزاحة الفساد، أم نحتاج إلى شيء أخر يدعم عملية الشفافية؟ وإذا تم التحدث عن الشفافية كمصطلح بدون وجود مما

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Publication Date
Wed Dec 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
التدقيق الداخلي وأثرة في الحد من ظاهرة غسيل الأموال
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Still Financial institutions, including banks, a key target for money launderers to transfer illicit funds to the legitimate funds and by weaknesses in the internal audit procedures applied in the banks or through a lack of legal structure to combat this phenomenon in addition to the procedures by other regulations                                                                

T

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Publication Date
Wed Jun 18 2025
Journal Name
دار اراء للطباعة والنشر والتوزيع
الصحة النفسية في عصر التكنلوجيا تحليل للتحديات والفرص المتاحة
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بكل تواضع، نقدم لكم هذا الكتاب بعنوان "الصحة النفسية في عصر التكنولوجيا: تحليل للتحديات والفرص المتاحة". يسعى الكتاب إلى إلقاء الضوء على العلاقة المعقدة بين عالمنا الرقمي المتنامي وصحة عقولنا وقلوبنا. نعيش في زمن يشهد تغييرات كبيرة نتيجة التقدم التكنولوجي، حيث أصبحت الأدوات الرقمية جزءًا أساسيًا من حياتنا اليومية، تؤثر في أساليب تواصلنا، تعلمنا، وتفاعلنا مع محيطنا. لذا، يصبح من الضروري فهم تأثير هذه التقنيا

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