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
Mon Jun 09 2025
Journal Name
Journal Of Physical Education
Standard Levels of Modern Administration for the Iraqi Central Olympic Committee's Olympic Federations
...Show More Authors

The problem of the research lies in the lack of standard levels for modern administration as a guide for evaluating weaknesses and strengths as well as finding solutions. The aim of the research lies in identifying standard levels for modern administration in Iraqi central Olympic committee and international federations. The subjects were (24) Olympic committee' federations. All procedures were standardized to fit our modern administration work. The data was collected and treated using proper statistical operations. The researcher concluded standard levels for modern administration in international federation of the Iraqi Olympic committee, in addition to that he concluded that most administrations levels ranged within four levels (good, fa

... Show More
View Publication Preview PDF
Publication Date
Wed Nov 14 2018
Journal Name
Arab Science Heritage Journal
تأثير تأثير الحضارة الأندلسية في الحضارة الأوربية انتقال أصناف من الأغذية إلى مائدة الطعام الأوروبية
...Show More Authors

       The progress that happened in Andalusia civilization was affected  by Arabic through taking care of agriculture by entering of new kinds of planets that were more important as political sides which led to prominence new kinds of food transported to Europe that had showed a real reflect of how chat of civilization among people who had lived in various ages until now

View Publication Preview PDF
Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
The Level of Administrative Work Quality of Private Schools Principals at Southern Governorates of Palestine form the Teachers Point of View
...Show More Authors

The study aimed at identifying the level of administrative work quality of private Schools principals at Southern Governorates of Palestine from the teachers' point of view in their schools. To achieve the objectives of this research, a questionnaire was prepared by the researcher consisted of (28) items. It was applied to a sample of (350) teachers. The researcher adopted the descriptive-analytical approach. The results of the study showed that the degree to which principals of private schools in the southern governorates of Palestine practice Administrative Work Quality from the viewpoint of their teachers was very high, with relative weight (85.00%). The results also showed that there are statistically significant differences at the l

... Show More
View Publication Preview PDF
Publication Date
Mon Oct 01 2007
Journal Name
Journal Of Educational And Psychological Researches
تقويم طرائق التدريس والتقنيات التربوية والأختبارات التحصيلية لدى أعضاء الهيئة التدريسية في جامعتي بغداد والنهرين
...Show More Authors

أن أزدياد أعداد الطلبة في معظم دول العالم ، والتوسع في التعليم العالي ، أدى الى أستيعاب أعداد كبيرة في المؤسسات التعليمية من حملة الشهادات العليا الماجستير خاصة والدكتوراه ، وأن برامج الدراسات العليا وضعت لأعداد باحثين مختصين في مجالات عدة منها التدريس وما يتطلبه من مهارات مختلفة ، فأن قسماً منهم ليست لديه المعرفة النظرية والتطبيق العملي والمهارات اللازمة لأستخدام طرائق التدريس والتقنيات التربوية أث

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
التعايش السلمي في الاسلام بين التنظير والتطبيق عهد الامام علي (عليه السلام) للاشتر النخعي / انموذجا
...Show More Authors

     Peaceful coexistence is not seen as a new topic of secretions of modern civilization, a requirement to solve the problems of our era or one of the indications of urgent immediate needs, rather, tolerance is considered basis for building a state. Therefore, we can touch on the principles and basics of tolerance in the Holy Qur’an, the speeches of the Messenger (may God bless him and grant him peace) and his hadiths, and the principle of brotherhood that he established

View Publication Preview PDF
Publication Date
Sat Nov 10 2018
Journal Name
Journal Of Planner And Development
(دور الوعي البيئي لدى الأسرة العراقية في التخلص من النفايات الصلبة) (مدينة الرمادي – حي العزيزية)
...Show More Authors

View Publication Preview PDF
Publication Date
Mon Nov 19 2018
Journal Name
Arab Science Heritage Journal
مصطلح مصطلح (i3-gal2) في ضوء نصوص مسمارية غير منشورة من عصر سلالة أور الثالثة
...Show More Authors

The verbal formula // i3-gal2 //is a commonly form in the written Sumerian economic texts, starting from the early dynastic period (2900-2372 BC), ending with the Ur III dynasty (2112-2004 BC).  This formula has appeared either without infixes, or accompanied by infixes like / in-da-gal2/,  corresponded in Akkadian the formula: ibaššu ,which is  means "to found, to Storage ", As to the formula / da / come to indicate "to found with, to storage with--).

View Publication Preview PDF
Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
تصـمـيم ومــحـاكاة سلسلة التجـهـيز الالكترونية دراسـة حـالة في الـشـركة الـعـامـة للـصـناعـات الـصـوفية – مـعـمل 1 أيـار
...Show More Authors

Supply Chain Management (SCM) attempts to a create a synchronization of the firm’s processes and those of the supplier to match the flow of materials, services, and information with the customer demand. Due to its importance, the SCM has become inevitable to modern companies. Therefore this research work has been conducted to set a theoretical and applied basis to assist the 1 AYAR factory in adopting the Electronic Supply Chain (e-SC).  To accomplish that the searchers applied many tools such as: quantitative and qualitative analysis, process analysis, Visual Basic software, Monte Carlo Simulation to simulation the designed supply chain to compare its performance against the actual performance of the current supply chain

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Oct 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Institutional Performance Assessment using a model of the European Foundation for Quality Management (EFQM) A case study at an organization
...Show More Authors

The study aims to use the European Excellence Model (EFQM) in assessing the institutional performance of the National Center for Administrative Development and Information Technology in order to determine the gap between the actual reality of the performance of the Center and the standards adopted in the model, in order to know the extent to which the Center seeks to achieve excellence in performance to improve the level of services provided and the adoption of methods Modern and contemporary management in the evaluation of its institutional performance.

The problem of the study was the absence of an institutional performance evaluation system at the centre whereby weaknesses (areas of improvement) and st

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
أثر استراتيجية التدريس التبادلي في اكتساب مهارة قراءة الخريطة الجغرافية لدى طالبات الصف الخامس الأدبي
...Show More Authors

The aim of this study is to find out the effect of reciprocal teaching   on the fifth literary class pupils in acquiring the skill of geographic map reading. The researcher uses the partial experimental design/pre- post-test for two equivalent control and experimental groups.

   The population of the study is represented by the fifth literary class pupils at a school of the Directorate of Education /Baghdad Karkh second. The sample is selected randomly as section (A) the experimental group and section (C) the control group. The sample total number is (60) pupils, (30) pupils for each group. The two groups are equalized in the following variables: IQ, age and the pupils’ previous geog

... Show More
View Publication Preview PDF