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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 Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
The Extent to Which Future Skills are Employed During Teaching from the Viewpoint of Students of Islamic Studies and their Relationship to Students' Attitude towards Future Profession
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The research aims to identify the relationship between employing future skills during teaching from the viewpoint of students of Islamic studies at the Northern Border University, as well as their attitudes towards future professions. The researcher employed the correlational descriptive approach. The tools were a questionnaire for employing future skills, and a scale for the attitude towards the future profession. The two research tools were applied to a random sample of (242) male and female students from the department of Islamic Studies, College of Education and Arts. The findings showed that the total level of employing future skills and their three axes during teaching was average. It was also found that the attitude towards future

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Publication Date
Thu Jan 01 2015
Journal Name
مجلة كلية الادارة والاقتصاد للدراسات الاقتصادية
دور الاجراءات والتشريعات الضريبية في التهرب الضريبي
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تعد الضريبة مصدراً مهماً لتحقيق الاهداف الاقتصادية والاجتماعية والسياسية للدولة ولذلك فان مشكلة التهرب الضريبي تعد اهم المشاكل التي ينبغي معالجتها من خلال معرفة اسبابها . ان وجود مشكلة التهرب الضريبي في العراق يرتبط بمجموعة من الاسباب والدوافع الكامنة وراء ظهور هذه المشكلة والتي لا نستطيع ان نلقي بتباعها على تخلف النظام الضريبي من حيث تشخيص الاختلالات في الادارة الضريبية تارة بل يجب ابراز عيوب التشريع الض

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Publication Date
Mon Jan 01 2018
Journal Name
مجلة كلية الآداب
العمود الومضة وتجلياته في الشعر العراقي المعاصر
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Publication Date
Sat Jan 05 2019
Journal Name
Journal Of Planner And Development
اتجاهات النظام الحضري في العراق 1957- 2010
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Publication Date
Sun Nov 11 2018
Journal Name
Arab Science Heritage Journal
تحصينات تحصينات بغداد الشرقية في العصر العثماني
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The wall of Eastern side considers one of the important prominence architect sign of Baghdad city through Abbasid era , it is surrounded by many shops, houses , the work had started in the period of caliph( Al-Mustathher Billah )

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Publication Date
Mon Mar 01 2021
Journal Name
المجلة العلمية للتكنولوجيا وعلوم الاعاقة
التكنولوجيا الحديثة ودورها في تعليم اصحاب الهمم
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يعد الاهتمام بأصحاب الهمم مطلب ديني لجميع الأديان ومطلب اجتماعي لانهم جزء أساسي من المجتمع ينبغي ان يحصلوا على فرصتهم وحقوقهم كباقي افراد المجتمع، فضلا عن كونه مطلب تربوي، إذ يعاني التلاميذ أصحاب الهمم من مشكلات عديدة وذلك لا سباب ترجع لخصائصهم وصفاتهم الخاصة التي ولدوا بها أو اكتسبوها بعد الولادة لسبب من الأسباب، لذا نجدهم يعانون من صعوبات في اكتساب المهارات والخبرات الحياتية بصورة عامة والتعليمية بصورة

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Publication Date
Wed Jan 02 2008
Journal Name
Political Sciences Journal
اشكالية بناء ثقافة مشاركة في الوطن العربي
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اشكالية بناء ثقافة مشاركة في الوطن العربي

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Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
The Properties of Thermal Waves Affecting Iraq
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This research aims at studying each of the cold and hot thermal wavelengths affecting
Iraq for a minimum climatic course of 11 years beginning from 1992 till 2002. Three stations
were selected including the parts of Iraq surface: Mosul, Baghdad and Basrah.
The wave days were also connected with the related climatic elements represented by
the wind direction and speeds and the relative humidity. It was shown that Iraq is affected by
the rates of hot thermal wave lengths greatly compared to the rates of cold wavelengths. The
results suggested that the highest rate of hot and cold wavelengths recorded over Basra station
was (3.5) days for the cold and (5) days for the hot. While the lowest rates was at Mosul
station

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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
اسلوبية التصوير في شعر التصوف قراءة نقدية
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Publication Date
Tue Jan 01 2013
Journal Name
Journal Of The College Of Languages (jcl)
La (autoantonimia) Al-ḍdad en las lenguas, según la lingüística moderna
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Los lingüistas no árabes suelen quedar perplejos a la hora de  interpretar el  fenómeno de Al-ḍdad, −normalmente traducido en español como palabras  autoantónimas (1)− en la lengua árabe, en el que los arabistas, y entre ellos los españoles, han quedado sombrosos ante este fenómeno. El jefe del tribunal de la defensa de mi tesis me pidió que le explicara este fenómeno según mi teoría “El esquema básico de la referencia”; pues me dijo que no podía  imaginar que una palabra tuviera dos significados opuestos, y en ese momento le expliqué la palabra albayn  البين que significa la separación,  o la relaciónel enlace que comentar

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