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
Wed Nov 14 2018
Journal Name
Arab Science Heritage Journal
المجتمع المجتمع الاسكندري: عاداته وتقاليده الاجتماعية في العصر المملوكي (648-923هـ/1250-1517م)
...Show More Authors

ان دراسة الاحوال الاجتماعية في الاسكندرية خلال العصر المملوكي امر مهم لاسيما ان الحياة الاجتماعية في مصر عامة والاسكندرية خاصة اتصفت بكونها بطيئة التغيير خلاف جوانب الحياة الاخرى التي اتصفت بسرعة تغير مجراها كما وان تاريخ الاسكندرية الاجتماعي كان زاخرا بالكثير من نواحي النشاط الانساني من ميادين العمل والتسلية والترفيه والاعياد والافراح فضلا عن تنوع عناصره السكانية وهذا ما سنتناوله ضمن محاور هذا البحث.

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
إضواء وآراء حول واقع ومستقبل إدارة الموارد البشرية صعبة المراس في منظمات الأعمال
...Show More Authors

The current researsh is aimed to pay attention on concept of human resources hard (Difficult) to manage. Such style of human resourcses has emerged to form anew challenge for busniess organizations.

Management such human resources entails first determing incentives of their behaviour models. Analyzing these models will be important to strategical management of them from work.

In nutshell, this researsh try to recommendation of contemporary literature about future of difficult (hard) human resources management.

View Publication Preview PDF
Crossref
Publication Date
Wed Aug 07 2019
Journal Name
Iraqi National Journal Of Nursing Specialties
Determination of the Cardiac Patients Knowledge toward Using Anticoagulant Medications at Missan Governorate Hospitals
...Show More Authors

Objective- the study aim to determine the cardiac patient knowledge about anticoagulant medications using and its relationship with demographic data(age. gender. level of education. occupational). Methodology- A descriptive study(quasi-experimental)design was carried out to determine cardiac patient knowledge consider to using anticoagulant medications . Starting from(1th Jun 2017 to5th October 2018).To achieve the objectives of the study, a non-probability sample (a purposive sample) consisted of random sample comprised of (30) patients were taken anticoagulant medications ..The measurement of patient knowledge were collected through the use of questionnaire which is related to patient knowledge toward using the anticoagulant medication

... Show More
View Publication Preview PDF
Publication Date
Mon Nov 12 2018
Journal Name
Arab Science Heritage Journal
المساواة المساواة بين الرجل والمرأة في ضوء القرآن الكريم دراسة تفسيرية ـ موضوعية
...Show More Authors

 It was the most important weapons that were used during the long cultural war standing against Islam, it is interesting colonists Muslim women special attention, and directed to lure women rebellion against religion, and go out on their own teachings in this religion,

View Publication Preview PDF
Publication Date
Thu Dec 13 2018
Journal Name
Arab Science Heritage Journal
تخطيط تخطيط عمارة المدن الإغريقية "دراسة تخطيطية ورؤية تاريخية في ملامح الحضارة الإغريقية"
...Show More Authors

The architecture Greek first civilizations, which focused on the design and planning of cities taking into account the percentages aesthetic and artistic forms beautiful and characterized Greek civilization styles three league and Ionian and Corinthian, has launched these names on this models relative to the form of

View Publication Preview PDF
Publication Date
Wed Jan 01 2025
Journal Name
International Journal Of Research In Social Sciences And Humanities
توظيف الذكاء الاصطناعي في العلوم الإسلامية وخدمة الدين الإسلامي وكيفية تجنب التحيز فيه
...Show More Authors

يُعد موضوع الذكاء الاصطناعي اليوم أحد أبرز القضايا التي تشغل الباحثين في التكنولوجيا العالية والدقيقة ، وكذلك في باقي الحقول الأخرى نظراًّ لربطها بالمنتجات والخدمات البشرية من أجل تقديم عدة مساهمات الغرض منها تبسيط وتسهيل الحياة الانسانية في مختلف المجالات في حالة إذا ما تم استخدامها وفق نهج أخلاقي مستدام يتضمن مجموعة من المبادئ كالعدالة والموضوعية والشفافية والمساءلة والمساواة ، وهي مبادئ تهدف بشكل عام

... Show More
Publication Date
Thu Jul 02 2009
Journal Name
Journal Of Educational And Psychological Researches
التكيف للحياة الجامعية وعلاقته بالصف الدراسي لدى طالبات الاقسام الداخلية في الجامعة المستنصرية
...Show More Authors

يواجه الكثير من الافراد مشكلات في التكيف، خاصة الطلبة الذين ينتقلون من المرحلة الدراسية الثانوية الى المرحلة الجامعية، حيث يرافق هذه البيئة الثقافية الاجتماعية العديد من الضغوط والمواقف التي تحتم على الطالب الوصول الى تكيف مثالي.

ان التعليم الجامعي يوفر مجالات عديدة للتخصص تعمل على تحقيق طموحات الشباب التي تناسب قدراتهم وميولهم واهتماماتهم، وهو بذلك يمثل نوعية من التعليم تختلف عن النم

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 01 2018
Journal Name
Journal Of The College Of Languages (jcl)
הסיפור העברי באמריקה ברבע השני של המאה ה-20 הסופר שמעון הלקין כדוגמה
...Show More Authors

                                      הסיכום

          הסיפורת העברית באמריקה, הייתה קשורה בסביבה מסויימה. גם כן היא קשורה בנושאים מסויימים, ורובם היו מדברים על חיי היהודים באמריקה.

            דמותו של שמעון הלקין קבועה בנפשם של המבקרים כזו של משורר בעי

... Show More
View Publication Preview PDF
Publication Date
Wed Jun 01 2022
Journal Name
Baghdad Science Journal
Assessment of Air Pollution around Durra Refinery (Baghdad) from Emission NO2 Gas at April Month
...Show More Authors

Nitrogen dioxide NO2 is one of the most dangerous contaminant in the air, its toxic gas that cause disturbing respiratory effects, most of it emitted from industrial sources especially from the stack of power plants and oil refineries. In this study Gaussian equations modelled by Matlab program to state the effect of pollutant NO2 gas on area around Durra refinery, this program also evaluate some elements such as wind and stability and its effect on stacks height. Data used in this study is the amount of fuel oil and fuel gas burn inside refinery at a year 2017. Hourly April month data chosen as a case study because it’s unsteady month. After evaluate emission rate of the all fuel and calculate exit velocity from

... Show More
View Publication Preview PDF
Scopus (20)
Crossref (8)
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