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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
Thu Oct 25 2018
Journal Name
Journal Of Planner And Development
(الاستخدامات الحضرية للمياه في المدن العراقية حالة الدراسة (مدن الفرات الأوسط
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Publication Date
Sun Apr 23 2023
Journal Name
مجلة الجامعة العراقية
قضايا أخلاقية في العل م اخلاقيات العلم والتكنولوجيا وتدريس الكيميا ء
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تهدف هذه المقالة إلى توضيح أخلاقيات العلم وضوابطه التي يجب على من يعمل في هذا المجال أن يكون متحلي بها حتى يحافظ على القيم والأخلاق الفاضلة والموروثة من الآباء والاجداد والنابعة من الصالحين والاخيار لديم ومة الحياة بأفضل وجه وكما يتمناه الكل وكذلك عدم تجاوز الحدود التي تؤدي إلى الأض ا رر بالمجتمع والبيئة . وتوضيح الحدود الغير مسموح بتجاوزها في مجال العلم والتكنولوجيا ومن هذه الأخلاقيات أو الضوابط التي يجب أن

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Publication Date
Mon Apr 04 2022
Journal Name
Journal Of Educational And Psychological Researches
Social Factors for Delaying the Age of Marriage among Working-Women at the University of Baghdad
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The phenomenon of delayed marriage triggered the intention of most researchers and specialists to reveal the social factors associated with the spread of this phenomenon in order to identify the characteristics of that phenomenon and the social factors resulting from it. Thus, the current research aims to identify the social factors most related to the delay in marriage age among working-women at the University of Baghdad, represented by family factors, economic factors-professional, psychological factors – subjective, and environmental factors. The researcher also aims to identify the differences in social factors associated with late marriage age for working women at the University of Baghdad in terms of the type of profession (teach

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Publication Date
Thu Dec 13 2018
Journal Name
Arab Science Heritage Journal
الدلالات الدلالات الصوتية للغة العربية في القران الكريم بين الحداثة والتجديد
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 A lot of researchers and specialists in language sciences have been agreed that Arabic language is on of living languages never disappear and keep pace with innovation and the challenges of the age and evolution civilization i.e any development in it’s connotations doesn't tzopped it (melted

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Publication Date
Wed Nov 28 2018
Journal Name
Arab Science Heritage Journal
جوانب جوانب من المعالجات البيئية والمناخية لعمائر الطين في الواحات الليبية
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This paper sheds light on aspects of environmental and climatic treatments in the groves mud existing in some Libyan oases. It reveals the architecture efforts and contributions to the adaptation of the construction and materials in order to organize the weather inside the building blocks to suit the nature of the human and his living in all seasons

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Publication Date
Thu Jun 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Using Genetic Algorithm to Estimate the Parameters of the Gumbel Distribution Function by Simulation
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In this research, the focus was on estimating the parameters on (min- Gumbel distribution), using the maximum likelihood method and the Bayes method. The genetic algorithmmethod was employed in estimating the parameters of the maximum likelihood method as well as  the Bayes method. The comparison was made using the mean error squares (MSE), where the best  estimator  is the one who has the least mean squared error. It was noted that the best estimator was (BLG_GE).

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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of The College Of Languages (jcl)
Hicri Dede (1877-1952)
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Asil adi Mahmeut olup mashlasi “ Hicrî “ dir . Ihvânî “ zümresine intisabi dolayısiyle “ Dede “ Lakabiyle anılır . Takriben  H. 1297 yılında Kerkük ‘ te doğmuş . Babası  H. 1305 Senesinde vefat eden Molla Ali Efendi ‘ dir .

       Dedesi Nazîrî dede ise zamanmin ileri gelen şâirlerinden olup kayser adli bir oğludur .  (1)

        Diğer bir kaynağa gore “ Hicrî  Dede H. 1295 yılında Kerkük ‘te doğamuştur . Tanınmış şâir Nazîrî Dede ‘ nin torunudur . Babası Molla Ali Efendidir” . (2)

      

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
المشكلات الاجتماعیة لذوي الاحتیاجات الخاصة (المسنین) دراسة میدانیة في مدینة بغداد
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The present study deals with the social work and the social problems which
the Elderly who lives in the house of special needs suffer from . this study aims to
shed light to the most important social problems which they suffer from inside and
show their relationship and interaet with each ofher and what we can see about that
intereact either negative or positive relationship . Its scientific importance include
adding a new study in the field of take care of the Elderly . and that will enrich the
scientific field with agood knowledge . Becouse the studies in this part was little ,
but the scientific and practical importance of this study presents by the results and
specify of the important problems . In addition to

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Publication Date
Thu Jul 02 2009
Journal Name
Journal Of Educational And Psychological Researches
توظيف رســوم الاطفال كوحدات تصميمية تعليمية في اقمشة ستائر رياض الاطفال
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مشكلة البحث

ان التصميم هو توالد افكار عدت اساس له حيث انها اشياء لها معنى لامور اقتضت الايعاز باعداد هذه التصاميم، اما المصمم فهو الشخص الملم بمباديء واسس التصميم من اجل تنفيذ هذه الافكار بطرق علمية مدروسة، الا ان هناك سؤالا يطرح هل بالامكان لاي شخص ان يرسم فكرة تصميمية؟

الجواب هو نعم فالتصميم ليس مقتصرا على المصمم فحسب بل ان باستطاعة أي شخص ان يعبر عن ما بداخله من افكار سواء ك

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
الشخصیة النرجسیة وعلاقتھا بالسلوك الایثاري لدى الطلبة المتمیزین في ثانویات المتمیزین
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This study aimed to investigate the relationship between narcissistic
personality and altruistic behavior for a subject of (307) gifted high schools
students, including (139)male and (168) female students ,both the scale of
narcissistic personality and the scale of altruistic behavior (Hameed ,2002) were
checked for its validity and reliability ,and both the level of narcissism and the
level of altruism for the students were measured in compare to the medium average
and approved to be statistically significant at (0.05) level.
Results showed that there were no significant differences in the altruistic
behavior between males and females ,results showed significant differences in
narcissism levels between males a

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