Preferred Language
Articles
/
alkej-347
Experimental and Numerical Research on Flow-Induced Vibration in Valves
...Show More Authors

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).

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Jan 06 2023
Journal Name
مجلة الباحث الاعلامي
مواقع الويب ودورها في بناء الصورة الذهنية للمنظمات الرياضية \ دراسة مسحية
...Show More Authors

Publication Date
Sun Jul 03 2011
Journal Name
Journal Of Educational And Psychological Researches
المشكلات التي تعاني منها المرأة العراقية الأرملة في ظل الظروف الراهنة
...Show More Authors

This research aims at identifying problems  that the  Iraqi widow woman suffers from. The research is limited to a Sample of terrorism victims widows which is up to (70) widows from Al-Amal center for widows and orphans care in Baghdad.                                                                                <

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2012
Journal Name
Journal Of Educational And Psychological Researches
معوقات استخدام الطرائق الحديثة لتدريس مواد اللغة العربية في المرحلة الإعدادية
...Show More Authors

objective of this research is to identify some of the obstacles that face secondary school teachers of the Arabic language courses in using modern teaching methods in class.

The research focuses on secondary school teachers of the Arabic language courses at the central region of Nineveh Governorate for the school year (2008-2009). 30 teachers out of 792, were randomly chosen to apply the research tool upon.

To fulfill the objective of this research, the researcher first surveyed a number of teachers , he then identified four categories of obstacles; obstacles related to school administrative system and environment, the teacher, courses and pupils, and the nature of teaching method

... Show More
View Publication Preview PDF
Publication Date
Wed Jun 01 2016
Journal Name
Journal Of The College Of Languages (jcl)
Estructura y el análisis de los personajes en la novela“ Sotileza ” de José María de Pereda
...Show More Authors

Resumen

    Sotileza , localismo santandrino de sutileza , es la parte más fina del aparejo de pescar donde va el anzuelo. Es la obra maestro de José María de Pereda.Su ambiente , el Santander viejo, anterior al año 50,evocado emocionadamente - emociόn romántica contenida en los trazos sobrios y firmes de un naturalism psicolόgico y paisajista,el Santander que el autor confiesa poseer en el fondo de su corazόn,«y tenerlo esculpido en la memoria de tal suerte que ,a ojos cerrados,me atrevería a trazarle con todo su perímetro y sus calles, y el color de sus piedras, y el número, y los nombres, y hasta las caras de sus habitantes».Dentro de la grandeza primaria de las criaturas de Pere

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 31 2019
Journal Name
Arab Science Heritage Journal
حفظ حفظ القرآن الكريم ودوره في تعليم اللغة العربية للناطقين بغيرها
...Show More Authors


When Allah has chosen Arabic language to be the eternal language of the Holly Qura'an, Qura'an was the original resource of the perfect grand Arabic

View Publication Preview PDF
Publication Date
Wed Nov 28 2018
Journal Name
Arab Science Heritage Journal
العالم العالم ابن خلدون ( ت 808 هـ ) (نظريته في السياسة والعصبية)
...Show More Authors

Ibn Khaldun is one of the best Arab Muslims scientists who participated in establishing Arabic Muslims heritage in all different disciplines & directions specially in sociology, neurological & his political theories which showed the development of Arabic philosophy in all scientific disciplines specially his introduction

View Publication Preview PDF
Publication Date
Wed Nov 28 2018
Journal Name
Arab Science Heritage Journal
اعتراضات اعتراضات الـخوارزمي الـنحوية في كتـابه التخمـير عـلى الـزمـخشـري ( قسم الأسماء )
...Show More Authors

Abook of alzmkchri (AL-Mefsal) considers one of the most book familiarities among grammarians whom begin to explain it importance kitab AL-Takhmair for Khwarizmi separated opinions in grammatical schools that dealt with.

View Publication Preview PDF
Publication Date
Sun Apr 01 2012
Journal Name
Journal Of Educational And Psychological Researches
تطوير واقع مقرر التطبيقات التدريسية في أقسام كليات التربية جامعة بغداد
...Show More Authors

The followers of the reality of the decision application faculty in departments of faculties of education of the University of Baghdad, it is noted that there are many shortcomings, which relate to Path, management, design, and evaluation, Coming from the work of the researcher as a teacher and supervisor, as well as to inform the researcher on many of the studies and literature, luck researcher on the article there are no courses are clear in theory and in practice the decision of the applications teaching, and often puts the teacher education curriculum, which lacks the link between the theoretical and practical, either in relation to its management, there is no office for the management and coordination at the University of Baghdad or

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 02 2006
Journal Name
Journal Of Educational And Psychological Researches
اثر العصف الذهني في تحصيل طلبة الصف الثاني متوسط بمادة التاريخ
...Show More Authors

 

أولاً : مشكلة البحث :

أن مشكلة البحث تتمثل بوجود حاجة لتحسين الطرائق والأساليب المتبعة في التدريس ولذلك اتجهت البحوث في مجال التربية وعلم النفس إلى تحديد طرائق التدريس المناسبة لتطوير التفكير.         

ومن هذه الأساليب الحديثة  العصف الذهني بوصفها من اكثر الطرق التي قد  تؤدي إلى تحفيز الطلبة وأثاره القدرات الإبداعية لديهم في حقول التربية والتعليم وا

... Show More
View Publication Preview PDF
Publication Date
Mon Oct 01 2012
Journal Name
Al–bahith Al–a'alami
Skills of Media Marketing of the Public Relations Staff: (University of Baghdad as a Model)
...Show More Authors

Departments and offices of public relations and media in any institution or company is the most important departments that reflect the results of their work negatively or positively on their reputation. This goes beyond the trust and credibility that its internal and external audiences will give it. Where such matter requires the staff, working in these departments and offices, to have communication skills that qualify them to do the role of marketing the communication message. Yet, the communication skills of public relations and media staff vary from person to person depending on the communication position. This skill has two criteria: Achieving the communication goal and the speed in achieving it as a number of skills

... Show More
View Publication Preview PDF
Crossref