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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
Sun Mar 30 2003
Journal Name
College Of Islamic Sciences
Scientific interpretation of the Holy Qur’an and its impact on belief and thought
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Praise be to God, Lord of the Worlds, and prayers and peace be upon the Master of Messengers, Muhammad and his family

The good and pure and after his companions

God Almighty said: ( ) Do they not contemplate the Qur’an? If it had been from other than God, they would have found in it much discrepancy. God Almighty has made the well-being of people and their lives linked to faith in it. So what is the need of people today to return to the Book of their Lord so that they may return to the right path that God intended for His servants so that they may attain sustenance? Security and the good life. How could it not be, when many of the nations of the world no longer see security or stability because their leaders and politic

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Publication Date
Tue Jun 01 2021
Journal Name
Journal Of The College Of Languages (jcl)
Definition of the verb in the form of the imperative mood (imperative) - general information about the verb in Russian: Определение глагола в форме повелительного наклонения (императива) - общая сведения о глаголе на русском языке)
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      The article examines the definition of the verb in the form of the imperative mood (imperative) _ general information about the verb in Russian .

       A verb in Russian is one of the parts of speech that unify all parts of speech, expressing the meaning of action, movement, process in grammatical forms of time, type, mood, face and voice. The imperative mood is a grammatical feature of the verb expressed through several forms of the verb that urges someone to do things. In other words, imperative mood or (imperative) : -  one of the single meaning of the form . The form of the imperative expresses a supplicatio

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Publication Date
Tue Jun 18 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Performance Measurement and Evaluated on The Lean Accounting
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At the last two decades , The environment has witnessed tremendous changes in many fields with the huge competition , various technological development and customer satisfaction , that are reflected in economic units a doption for lean production system.   

   Lean accounting that has appeared as a response for change occurred of economic units adoption for changes occurred of economic units adoption for lean production instead of wide production system , has devised new performance measures suitable for economic units adoption for lean ideas: and helping in providing suitable information about evaluating economic unit performance , these measures are divided into three levels , cell level,value flow level , a

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Publication Date
Wed Jun 30 2021
Journal Name
Journal Of Planner And Development
Urban wetlands and their impact on city sustainability
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Urban wetlands are one of the complex systems that provide many economic, social and environmental services to the city. In this research, the most important services provided by urban wetlands from the point of view of the urban planner were reviewed, and the types of these lands and their divisions according to the type of services provided by each type were presented. Environmental is represented in its ability to reduce the dangers of floods, mitigate the climate and reduce its negative impacts, purify water and deplete a lot of suspended impurities and pollutants, and social services such as recreational areas and beautiful landscapes that inspire joy and reassurance in the soul, as well as cultural areas and sports activities for m

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
The Effect of Social Responsibility initiatives in Financial Performance on economic unit and create value for it
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        Many of researchers have written about social responsibility and business strategy and competitive advantage, and they have given particular attention to the relationship between economic and social responsibility , but what is missing in this aspect is how the economic units that use their core competencies to advance social responsibility initiatives so that they can achieve a significant competitive advantage and create value for it ?

The current research aims to verify the view that "the economic and social objectives in the long term is not contradictory in nature but complementary objectives essential", as well as make sure that the s

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Publication Date
Fri Nov 09 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Effectiveness of Physical Education Program on the Domains of the University Students, Attitudes toward Physical Fitness
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Objectives: To determine the effectiveness of physical education program on the domains of the university
students attitudes of physical activity and health, physical activity and mental health, physical activity and nutrition
toward physical fitness.
Methodology: A quasi-experimental design is carried out throughout the present study with the application of
test-retest approach through the period from February 3rd 2013 to June 30th 2013. The study is conducted on
purposive sample of(40) Undergraduate Students at the College of Science University of Baghdad . The sample is
Consisted of (20) males and (20) females. Questionnaire of two main parts, Personal and demographic
information and students' attitudes about phys

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Publication Date
Mon Dec 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Analysis of the Effects of Aggressive Shot Peening on Fatigue Life of 7075 – T6 Aluminum Alloy
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 For many years controlled shot peening was considered as a surface treatment. It is now clear that the performance of control shot peening in terms of fatigue depends on the balance between its beneficial (compressive residual stress and work hardening) and beneficial effects (surface hardening).

The overall aim of this paper is to study the effects of aggressive shot peening on fatigue life of 7075 – T6 aluminum alloy. The fatigue life reduction factor (LRF) due to the aggressive shot peening was established and empirical relations were proposed to describe the behavior of LRF, roughness and fatigue life. The benefits of shot peering in terms of fatigue life are dependent on the shot peening time (SPT).

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Publication Date
Mon Mar 11 2019
Journal Name
Baghdad Science Journal
Study the Effect of Cold Plasma on the Nonlinear Properties of Polymeric Membranes Rod Amine (R3Go)
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The nonlinear optical properties for polymeric (PMMA) doping with dye Rhodmine (R3Go) has been studied .The samples are prepared by normal polymerization method with concentrations of 5x10-5mol/l and a thickness of 272.5µm.

                         Plasma effect was studied on samples prepared before and after exposure to the Nd: YAG laser for three times 5, 10 and 15 minutes. Z-Scan technique is used to determine the nonlinear optical properties such as; refractive index (n2) and the coefficient of nonlinear absorption (β). It was found that the nonlinear properties is change by increasi

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Publication Date
Thu Dec 01 2022
Journal Name
Iraqi Journal Of Physics
Study the Effect of Dielectric Barrier Discharge (DBD) Plasma on the Decomposition of Volatile Organic Compounds
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Recently, research has focused on non-thermal plasma (NTP) technologies as a way to remove volatile organic compounds from the air stream, due to its distinctive qualities, which include a quick reaction at room temperature. In this work, the properties of the plasma generated by the dielectric barrier discharge (DBD) system and by a glass insulator were studied. Plasma was generated at different voltages (3, 4, 6, 7, 8 kV ) with a fixed distance between the electrodes of 5 mm, and a constant argon gas flow rate of (2.5) I/min. DBD plasma emission spectra were recorded for each voltage. The Boltzmann plot method was used to calculate the electron temperature in the plasma ( ), and the Stark expansion method was used to calculate the elec

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Publication Date
Sun Sep 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Study the Effects of Machining Parameters on Surface Roughness for Free Form Surface Using Taguchi Method
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The surface finish of the machining part is the mostly important characteristics of products quality and its indispensable customers’ requirement. Taguchi robust parameters designs for optimizing for surface finish in turning of 7025 AL-Alloy using carbide cutting tool has been utilized in this paper. Three machining variables namely; the machining speeds (1600, 1900, and 2200) rpm, depth of cut (0.25, 0.50, 0.75) mm and the feed rates (0.12, 0.18, 0.24) mm/min utilized in the experiments. The other variables were considered as constants. The mean surface finish was utilized as a measuring of surface quality. The results clarified that increasing the speeds reduce the surface roughness, while it rises with increasing the depths and fee

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