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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 Nov 14 2018
Journal Name
Arab Science Heritage Journal
صلاة فقه الحديث في قوله (صلى الله عليه وسلم) " صلاة في مسجدي هذا أفضل من ألف صلاة مما سواه إلاّ المسجد الحرام"
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Prayer It is the second pillar of Islam, which is what Allaah erases sins, the Prophet, peace be upon him say: "Do you see if the river at the door of you wash it every day five, what it says: it keeps dirt," they said, does not keep the dirt something, He said: «That is like the five daily prayers, Allaah erases sins", Bukhari (1/112), and the places and times supervised thanks to worship them, was to pray at the three mosques (the Grand Mosque and the Prophet's Mosque and the Al-Aqsa Mosque) private virtue from the rest of the mosques and this virtue include the obligatory prayers and Voluntary Prayers.

 

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Publication Date
Thu Jan 04 2018
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
CHIA SEEDS ARE USED TO PRODUCE GLUTEN-FREE BISCUITS: CHIA SEEDS ARE USED TO PRODUCE GLUTEN-FREE BISCUITS
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White and black chia seeds were used in some food products, such us gluten –free biscuits processing by using rice flour and chia seeds (white and black) with these amonths 112.5, 74.25, 56.25, 27.5 g with 27.5g of quinoa seeds for treatments 1, 2, 3 and 4 respectively, and comparison sensitively with the control treatment which has no additions including the appearance and homogenization of the product, surface cracks, softness, taste and flavor, core color and the specific volume, some microbiological tests were performed for biscuit product after storage for 4 months at 30 and 50°C including bacterial total count and fungal and yeast count, results showed that there weren’t any observation of bacteria or yeast or fungal growth at

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Publication Date
Tue Dec 31 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
USE OF IMMOBILIZED L-ARABINOSE ISOMERASE FOR PRODDUCTION OF TAGATOSE: USE OF IMMOBILIZED L-ARABINOSE ISOMERASE FOR PRODDUCTION OF TAGATOSE
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L-arabinose isomerase from Escherichia coli O157:H7 Was immobilized with activated Bentonite from local markets of Baghdad, Iraq by 10% 3-APTES and treated with 10% aqueous glutaraldehyde, the results refer that the yield of immobilization was 89%, and pH profile of free and immobilized L-arabinose isomerase was 7 and 7.5 and it is stable at 6-8 for 60 min respectively, while, the optimum temperature was 30 and 35°C and it was stable at 35 and 40°C for 60 min but it loses more than 60 and 30% from its original activity at 50°C for free and immobilized L-arabinose isomerase respectively. Immobilized enzyme retained its full activity for 32 day, but it retained 73.58% of its original activity after storage for 60 d

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Publication Date
Sun Oct 31 2021
Journal Name
مجلة علوم الرياضة الدولية
تأثير تدريبات خاصة وفق جهاز الكتروني مصنع في التحكم بتوازن القوة للرجل الأمامية و الخلفية أثناء التقدم و الرجوع في رياضة المبارزة
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Publication Date
Tue Nov 13 2018
Journal Name
Arab Science Heritage Journal
فقه فقه الحديث في قوله (صلى الله عليه وسلم) " صلاة في مسجدي هذا أفضل من ألف صلاة مما سواه إلاّ المسجد الحرام"
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Prayer It is the second pillar of Islam, which is what Allaah erases sins, the Prophet, peace be upon him say: "Do you see if the river at the door of you wash it every day five, what it says: it keeps dirt," they said, does not keep the dirt something, He said: «That is like the five daily prayers, Allaah erases sins", Bukhari (1/112), and the places and times supervised thanks to worship them, was to pray at the three mosques (the Grand Mosque and the Prophet's Mosque and the Al-Aqsa Mosque) private virtue from the rest of the mosques and this virtue include the obligatory prayers and Voluntary Prayers

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Publication Date
Tue Dec 15 2015
Journal Name
مجلة العلوم الاقتصادية والادارية
‫تحديد أثر أخلاقيات العلاقات العامة في القرارات الإستراتيجية دراسة وصفية تحليلية لآراء عينة من القيادات الإدارية في وزارة التعليم العالي والبحث العلمي
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يختلف دور العلاقات العامة (PR) وأهميتها من مجتمع إلى آخر، تبعاً لاختلاف ثقافات هذه المجتمعات عموماً, ولاختلاف القيم الأخلاقية المعمول بها من ممارسيها في منظمات هذه المجتمعات, فالعلاقات العامة في المجتمعات المتقدمة وبعض الدول النامية قد خطت خطوات جبارة ووصلت إلى مرحلة المساهمة في التخطيط الاستراتيجي وعملية اتخاذ القرار, في إطار التزام إداراتها بقيم ومعايير أخلاقية محددة لممارسيها, وبالمقابل نجد أن تطبيقها في

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Image Steganography by Using Multiwavelet Transform
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Steganography is the art of secret communication. Its purpose is to hide the presence of information, using, for example, images as covers. The frequency domain is well suited for embedding in image, since hiding in this frequency domain coefficients is robust to many attacks. This paper proposed hiding a secret image of size equal to quarter of the cover one. Set Partitioning in Hierarchal Trees (SPIHT) codec is used to code the secret image to achieve security. The proposed method applies Discrete Multiwavelet Transform (DMWT) for cover image. The coded bit stream of the secret image is embedded in the high frequency subbands of the transformed cover one. A scaling factors ? and ? in frequency domain control the quality of the stego

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Publication Date
Sun Jun 01 2008
Journal Name
Journal Of The College Of Languages (jcl)
The Iraqi Learners' Production Of rp Clipped Vowel
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Within connected speech, RP speakers tend to shorten stressed long vowels end diphthongs in pre. Forties consonants in the same syllable on the basis of complementary Distribution, i.e., the phonological environment decides the influence of the forties plosives and fricatives, as far as they are in find position preceded by stressed long vowels and diphthongs, or particular voiced consonants plus vowels. The Iraqi learners, then, face.

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Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
إسهامات علماء العرب والمسلمين القدامى في إثراء علوم الرياضات
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     Arab and Muslim scholars have made influential contributions to the development of mathematics by providing it with many achievements and inventions. This research presents the most important of these achievements and assistance in mathematics during the period of the Islamic Renaissance for different Arab and Muslim Scholars. One of the clearest and most prominent examples of these achievements is the establishment of the science of algebra and the discovery of zero and added to the numbers by the Muslim Scholar of Al-Khwarizmi, which facilitated the solution of many arithmetic problems and issues to this day.

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Publication Date
Mon Nov 12 2018
Journal Name
Arab Science Heritage Journal
البرجوازية البرجوازية المسلمة في الشرق الادنى خلال العصر العباسي
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The shortcomings of the Muslim regime were however, became more obvious in later periods. Under the first Abbasids, the Muslims bourgeoisies were still a new class, rising in the social hierarchy of the caliph empire. It became even powerful class and a factor to reckon with

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