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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 Jul 01 2015
Journal Name
Al–bahith Al–a'alami
Methods of Arab TV Programs Production
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This research investigates the methods of producing Investigative Arabic Television Programs that are able to prove its existence during a short period of time as a form of Television programs on Arab satellite channels growing in number and varied in content. The research aims to present qualitative and quantitative descriptions of the methods used in tackling the topics discussed in the program, and knowing whether they satisfy the conditions and scientific foundations for the research, investigation, analysis, and interpretation. The researcher uses the survey method and uses the tool of content analysis including a set of methodological steps that seek to discover the implied meaning of the research sample represented by the program

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Publication Date
Tue Dec 22 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
التحول نحو أساس الإستحقاق المحاسبي لتعزيز المساءلة وإدارة الموجودات الثابتة للقطاع العام في العراق
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The research aims to present and discuss the accounting bases adopted in accounting for fixed assets in the public sector with an emphasis on its importance in the area of ​​accountability and fixed assets management , based on a realistic problem associated with the use of cash basis accounting in the public sector in Iraq, which are difficult  to provide accounting information useful for many users , including the same units and regulatory departments for the purposes of accountability and management of those assets. Search tool has been the organization questionnaire, its results show the importance of financial reporting for provide accounting information about fixed assets relate to the units of the public sector in Iraq fo

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Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
The possibility of applying CAPP technology to improve the quality of the product
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     The research deals with A very important two subjects, computer aided process planning (CAPP) and Quality of product with its dimintions which identified by the producer organization, the goal of the research is to Highlight and know the role of the CAPP technology to improve quality of the product of (rotor) in the engines factory in the general company for electrical industries, The research depends case study style by the direct visits of researcher to the work location to apply the operational paths generated by specialized computer program designed by researcher, and research divides into four axes, the first regard to the general structure of the research, the second to the theoretical review, the t

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Publication Date
Wed Jul 01 2015
Journal Name
Journal Of Educational And Psychological Researches
مستوى التنمية المهنية لتدريسيي جامعة بغداد في ضوء مؤشرات الجودة الشاملة من وجهة نظرهم
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The present study aimed to know The teaching members’ level of the professional development at the University of Baghdad based on the indicators of the overall quality from their perspective;

The researchers used the descriptive and analytical approach the in order to achieve the purposes of research, the researchers designed questionnaire researched and consisted of 40 paragraph has the questionnaire submitted to the arbitrators and experts were verify the authenticity of the questionnaire and stability have been applied questionnaire on a range of teaching and Tdriciat Baghdad University, which reached the study sample (400) teaching and teaching of six colleges in the University of Baghdad equivalent

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Publication Date
Sun Apr 28 2019
Journal Name
Arab Science Heritage Journal
الظواهر الظواهر الاجتماعية في بغداد من خلال كتاب الظرف والظرفاء لابي الطيب الوشاء(ت320هـ)
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 the study of social phenomena in this direction is, the sign of deviousness to the segments of the circumstance with their conditions and circumstances, then pointed to the uniforms that they were adorned by the tortillas as well as shirt Safaf from good linen soft and touched the country and the good and others.

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Publication Date
Sat Sep 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
صياغة أهداف المحاسبة والتقارير المالية في ظل اختلاف المتغيرات البيئية أفكار مطروحة وأراء مقترحة
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المقدمة ومنهجية البحث

تتفق أغلب الأدبيات ومنها المحاسبية, بأن الخطوة الأولى في وضع وتقييم أي نظام إداري أو محاسبي هي في صياغة أهداف ذلك النظام لما لذلك من أهمية في توفير معيار للحكم على كفاءة التطبيق من عدمه.

وتعرف الأهداف بأنها (النهايات التي تعمل أو توجه النشاطات باتجاهها أو هي النهايات التي تطمح النشاطات تحقيقها). ( 1 ) ..,

 كما تعرف أيضا بأنها (الأ

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Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
The Degree of the E-Leadership Practice at Princess Nora Bint Abdul Rahman University of the Corona Pandemic
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The study aimed to identify the E-leadership practice at Princess Nora Bint Abdul Rahman University and to explore the obstacles that are facing the leaders in the implementation of E-leadership, in addition to find mechanisms to improve the practice of electronic driving at the university in light of the Corona pandemic. A descriptive analytical approach was used by depending on a questionnaire to collect the needed data. The study sample consisted of (139) heads of departments, attorneys' colleges and support Deanships universities. The study results showed that E-leadership employment recorded a medium to high degree. Especially at university, that publishing decisions electronically and uses technical means in providing its services.

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Publication Date
Wed Dec 29 2021
Journal Name
Al-khwarizmi Engineering Journal
Analysis of Magnetorheological Normally Close Directional Control Valve: Magnetorheological normally close directional control valve
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This valve is intended for use in valves for steering movement, using the qualities of the Magneto-rheological (MR) fluid to regulate the fluid, direct contact without the utilization of moving parts like a spool, a connection between electric flux, and fluid power was made, The simulation was done to employ the" finite element method of magnetism (FEMM)" to arrive at the best design. This software is used for magnetic resonance valve finite element analysis. The valve's best performance was obtained by using a closed directional control valve in the normal state normally closed (NC) MR valve, with simulation results revealing the optimum magnetic flux density in the absence of a current and the shedding condition, as well as the optimum

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Publication Date
Tue Dec 11 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Burden of Mothers’ Care for Children with Colostomy at Baghdad Medical City Teaching Hospital
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Objective(s): To assess the burden of mothers` care for child with colostomy and find out relationships between child and mother socio-demographic data with mothers` burden. Methodology: a descriptive study was conducted from 1 August 2013 to 1 September 2014. The sample consisted of 100 children and their mothers at Baghdad Teaching hospital in Baghdad city. A questionnaire was prepared based on the previous literature review, meeting mothers of children with colostomy, and the Zarit Burden Interview scale. Data has collected through the application of questionnaire and interview techniques. Results: T

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Publication Date
Fri Jun 01 2007
Journal Name
Journal Of The College Of Languages (jcl)
Molla Mehmet Sadık'ın Kerkük'teki Eskide Bulunan Taş Köprü Adlı El Yazısının İncelemesi Açıklaması
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Yaşıyan kuşağın unutulmaz aruz şairi tanınmış Hacı Mehmet Sadık. İzi
silinmez kaybin, bugünkü eski sitil şiirin gerçek sembolu olup yaşadığı bir çağa
yakın süre içinde yüzlerce ve yüzlerce beyit şiir söylemiş.
Her çevrede Türk doğup Türk yaşamak bahtıyarliğiyle övünen ozanımızın ,
seçkin bir çok şiirleri vardır.
Böylece kitap, dergi ve gazetelerde yayımlanmış sayısız şiirleri yanında
basıma hazır kitaplık şiir ve yazılarıda vardı. Gazetelerde yayımlanan şiirlerini
memleket dertlerine , değerli mert kişilerine gönüllerde yaşıyan ölülerine , yurdu
ve yurttaşı için iyilik güden devlet ve memleket büyüklerine ayırdığını
görmekteyiz.<

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