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
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
A Proposed Analytical Method for Solving Fuzzy Linear Initial Value Problems
...Show More Authors

     In this article, we aim to define a universal set consisting of the subscripts of the fuzzy differential equation (5) except the two elements  and , subsets of that universal set are defined according to certain conditions. Then, we use the constructed universal set with its subsets for suggesting an analytical method which facilitates solving fuzzy initial value problems of any order by using the strongly generalized H-differentiability. Also, valid sets with graphs for solutions of fuzzy initial value problems of higher orders are found.

View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Tue Jun 01 2021
Journal Name
Periodicals Of Engineering And Natural Sciences
Steganography using dual tree complex wavelet transform with LSB indicator technique
...Show More Authors

Image steganography is undoubtedly significant in the field of secure multimedia communication. The undetectability and high payload capacity are two of the important characteristics of any form of steganography. In this paper, the level of image security is improved by combining the steganography and cryptography techniques in order to produce the secured image. The proposed method depends on using LSBs as an indicator for hiding encrypted bits in dual tree complex wavelet coefficient DT-CWT. The cover image is divided into non overlapping blocks of size (3*3). After that, a Key is produced by extracting the center pixel (pc) from each block to encrypt each character in the secret text. The cover image is converted using DT-CWT, then the p

... Show More
Preview PDF
Scopus (6)
Crossref (5)
Scopus Crossref
Publication Date
Tue Dec 26 2017
Journal Name
Al-khwarizmi Engineering Journal
Fuzzy Wavenet (FWN) classifier for medical images
...Show More Authors

 

    The combination of wavelet theory and neural networks has lead to the development of wavelet networks. Wavelet networks are feed-forward neural networks using wavelets as activation function. Wavelets networks have been used in classification and identification problems with some success.

  In this work we proposed a fuzzy wavenet network (FWN), which learns by common back-propagation algorithm to classify medical images. The library of medical image has been analyzed, first. Second, Two experimental tables’ rules provide an excellent opportunity to test the ability of fuzzy wavenet network due to the high level of information variability often experienced with this type of images.

&n

... Show More
View Publication Preview PDF
Publication Date
Wed Oct 01 2008
Journal Name
Journal Of Educational And Psychological Researches
المكانة الاجتماعية لطفل الروضة بين اقرانه وعلاقتها ببعض المتغيرات في مدينة بغداد
...Show More Authors

استهدف البحث الكشف عن المكانة الاجتماعية لطفل الروضة بين أقرانه ، ودلالة الفروق في المكانة الاجتماعية لاطفال عينة البحث التي تعزي الى بعض المتغيرات من خلال الاجابة عن الاسئلة الاتية :

اولاً : ما المكانة الاجتماعية لدى اطفال الروضة بين اقرانهم ؟

ثانياً : ما علاقة المكانة الاجتماعية لدى اطفال الروضة ببعض المتغيرات و ذلك من خلال اختبار الفرضيات الصفرية الآتية :

... Show More
View Publication Preview PDF
Publication Date
Tue Apr 01 2008
Journal Name
Journal Of Educational And Psychological Researches
أثر أستعمال الأسئلة التحضيرية في أكتساب طالبات الصف الرابع العام للمفاهيم التاريخية
...Show More Authors

        يمر عالمنا المعاصر اليوم بمرحلة من التطور والتغيير السريعين لم يسبق له أن مر بهما فـي تاريخ البشرية ، ويشمل مظاهر الحياة  الأنسانية  والأقتصادية والعلمية والتربويـة والنفسية وغير ذلك . وتختلف سرعة هذا التغيير من مجتمع الـى مجتمع آخر , وأدى هذا الى تراكم كميات كبيرة من المعلومات .

         لقد أكد الكثير مـن التربويين أن التطور التكنولوجي فـي ال

... Show More
View Publication Preview PDF
Publication Date
Fri Aug 15 2008
Journal Name
اطروحة دكتوراه
الاقليمية الدولية الجديدة في عالم ما بعد الحرب الباردة : انموذج آسيا الباسفيك
...Show More Authors

The thesis discusses the concept of the new international regionalism that emerged after the growing effects and repercussions of globalization with its economic, political and security dimensions after the end of the Cold War and the crystallization of a different international system dominated by the United States of America, so that the major countries and actors in the international system realize the danger of globalization and move towards adopting regional arrangements to contain the negative effects of globalization. The Asia-Pacific model was chosen as a model for the study.

View Publication
Publication Date
Sat Jun 01 2013
Journal Name
Journal Of The College Of Languages (jcl)
Спортивная периодика Украины и Иракского Курдистана как средство становления национального единства в переходный период
...Show More Authors

In this subject article analyzed features of a sports indifferent countries during , article analyzed features of a sports media in different countries between social change politcheskih , transformation thematic area dedicated sports periodicals and the influence of these media on the formation of national identity .

Subject of comparative analysis research are sports print media in Ukraine and Iraqi Kurdistan .And highlight the sports as one of modem  Kurdish journalism in lraqi Kurdistan that emerged after the spring in 1991 which took her privacy in the field of journalism , and analysis with sports journalism in the era of the independent state of Ukнаraine in the early nineties of the past century .

View Publication Preview PDF
Publication Date
Sun Oct 09 2022
Journal Name
كتاب وقائع المؤتمر العلمي الدولي الثاني للعلوم الانسانية والاجتماعية / جامعة فردوسي مشهد
بقاء اثر التعلم بين التعليم الالكتروني والتعليم الحضوري في الرياضيات (دراسة مقارنة)
...Show More Authors

المستخلص: يهدف البحث الى التعرف على بقاء اثر المعلومة عن طريق الاجابة عن السؤال: ما مدى بقاء اثر التعلم بين التعليم الالكتروني والتعليم االحضوري ؟ تم تطبيق البحث في العام الدراسي( 2020-2021 م) في العراق. تم استخدام المنهج الوصفي بالاسلوب المقارن في عقد مقارنة بين التعليم الالكتروني والتعليم الحضوري. وكان مجتمع البحث من طلبة المرحلة الرابعة كلية التربية للعلوم الصرفة – ابن الهيثم ,و العيتة من قسم الرياضيات الم

... Show More
Preview PDF
Publication Date
Mon May 01 2023
Journal Name
Warith Scientific Journal
اثر الاستقلالية والخبرة المالية والمحاسبية للجنة التدقيق في ملائمة قيمة المعلومات المحاسبية
...Show More Authors

ه رثا قيقحتلو ،ةيبساحملا تامولعملا ةميق ةمئلام يف قيقدتلا ةنجلل ةيبساحملاو ةيلاملا ةربخلاو ةيللاقتسلاا ثحبلا تايضرف رابتخلا ةمزلالا تانايبلا عمجل ةنابتسا ةرامتسا مادختساب ةثحابلا تماق ةساردلا فده ةللاد وذ رثأ دجوي(يهو ةيبساحملاو ةيلاملا ةربخلل ةيئاصحإ ةللاد وذ رثا دجوي( ، )ةيبساحملا تامولعملا ةميق ةمئلام ىلع قيقدتلا ةنجل ةيللاقتسلا ةيئاصحا )ةيبساحملا تامولعملا ةميق ةمئلام ىلع ( نم تنوكت ةنيع ىلع تعزو ث

... Show More
View Publication
Publication Date
Mon Dec 26 2022
Journal Name
Arab Science Heritage Journal
العمق الوجداني والانفعال العاطفي لدى شعراء القرنين السابع والثامن الهجريين في الأندلس
...Show More Authors

The Andalusi did not leave any poetic art without expressing his psychological and sentimental emotions and the depth of emotions and it sincerity. We found Andalusian translated his emotions into poetry and in many different subjects

View Publication Preview PDF