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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
Tue Feb 16 2016
Journal Name
The Iraqi Journal Of Agricultural Sciences
MEASURING VIBRATION AT TRACTOR PLATFORM , STEERING WHEEL AND SEAT EFFECTIVE AMPLITUDE TRANSMISSIBILITY FACTOR DURING OPERATION TILLAGE
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Field experiment conducted to measure vibrations on three axes longitudinal X, lateral Y and vertical Z on steering wheel, platform tractor and vertical vibration in seat tractor and seat effective amplitude transmissibility (SEAT) factor during operation tillage in silt clay loam soil with depth 18 cm in Baghdad. Split – split plot design under randomized complete block design with three replications least significant design 5 % used. Three factor were used in this experiment included two types of plows included chisel and disc plows which represented main plot, three tires inflation pressure was second factor included 1.1 ,1.8 and 2.7 bar, and three forward speeds of the tillage was third factor included 2.35 , 4.25 and 6.50 km/hr. Resu

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Publication Date
Thu Nov 01 2018
Journal Name
Curtin University
Gas hydrates investigation: flow assurance for gas production and effects on hydrate-bearing sediments
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This thesis was aimed to study gas hydrates in terms of their equilibrium conditions in bulk and their effects on sedimentary rocks. The hydrate equilibrium measurements for different gas mixtures containing CH4, CO2 and N2 were determined experimentally using the PVT sapphire cell equipment. We imaged CO2 hydrate distribution in sandstone, and investigated the hydrate morphology and cluster characteristics via μCT. Moreover, the effect of hydrate formation on the P-wave velocities of sandstone was investigated experimentally.

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Project Scheduling By using Goals Programming – An Applied Research In Modern Village Project (Residential Building Aspectin In Wasit Governorate)
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One of the most important challenges facing project management at present time is to ensure project accomplishment in spite of the specific restrictions like the specific time the financial resources specialized to do the project ; which require an accurate consideration for time and cost . the modern village project (residential building aspect) is one of the great project that ministry of agriculture is trying to do Wasit  governorate it is chosen as the work in this project is dilatory for that is being studied in term of some modern mathematical and scientific methods like critical path method (CPM)which is one of the project management and scheduling methods to know the time needed to accomplish residential building pro

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Publication Date
Wed Sep 08 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The effect of financial leverage on the market value of the shares of Iraqi commercial banks: An applied research in the Bank of Baghdad for the period (2010-2019)
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The aim of the research is to know the effect of financial leverage on the market value of the stock by applying it to a sample of private Iraqi commercial banks listed in the Iraqi Stock Exchange for the period (2010-2019) and to show the extent of that effect, based on the bank’s annual reports for the mentioned period through the use of financial leverage ratios represented b (Equity multiplier, cash balance ratio), its discussion, analysis, description, inferential description, and testing of research hypotheses,

A set of conclusions has been reached, the most important of which are: The research sample banks depend in their financial structures on borrowed funds in a greater proportion than their r

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Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The impact of empowerment strategies on the characteristics of work enrichment An exploratory research to the views of a sample of the leaders of the Ministry of Oil in Iraq
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The study aimed to investigate the relationship between empowerment strategies and their impact on the success of enrichment work, it included the dimensions of empowerment strategies (power, knowledge, information, rewards), The dimensions of Job enrichment are (Skill variety, Task identity, Task significance, Autonomy, Feedback). The study was conducted at the headquarters of the Iraqi Oil Ministry in Baghdad and was based on a sample of the leadership of the ministry of managers consisting of 215 people. The data were collected using the questionnaire method based on scientific standards adopted in previous st

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Publication Date
Mon Nov 10 2025
Journal Name
Al–bahith Al–a'alami
TOPICS OF PEACEFUL COEXISTENCE IN FOREIGN SATELLITE CHANNELS DIRECTED IN THE ARABIC LANGUAGE: (A Research Drawn from Master Thesis)
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This research deals with issues of peaceful coexistence in foreign satellite channels directed in the Arabic language, trying to get acquainted with the most prominent of these topics dealt with the programs subject to analysis and the method of dealing with them and the most used journalistic arts in that.

The research adopted the descriptive approach and the method of content analysis for the purpose of studying the research community represented by the program «Shabab Talk» “Youth Talk” in the German channel Deutsche Welle (DW) and the program «Beina Sam wa Amar» “between Sam and Ammar” in the American free channel, by designing the content analysis form to subject

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Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Dimensions of performance to provide nursing services: a comparative analytical research in Baghdad of Rusafa Health Organization
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     This research aims to study the performance of operations to provide nursing services, which included dimensions (quality, timeliness, leadership skills, behavioral manifestations, relationships with others, problem-solving and decision-making, job performance) and its effects in nursing performance. The research to prove the value of the performance of service delivery processes dimensions by nursing staffs working in Iraqi hospitals, nursing and measuring performance. To find out the nature of nursing services, and a comparison between hospitals to measure the extent of the application dimensional among themselves, and that by relying on the dimensions of a global study, which was measu

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Publication Date
Fri Apr 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Are flection Of Accounting for Contingent Assets, Liabilities and Provision on Faithful Representation Characteristic of Accounting Information
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Abstract                                                                     

This research aims to study the reflection of accounting for contingent assets and liabilities and provisions on Faithful Representation characteristic of accounting information, To achieve this goal has been questionnaire design has been distributed to research sample, which consists of (50) li

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
The Modrating Role of Dynamic Knowledge capabilies in Addressing Organizational Failures to Achieve Business Competitiveness: Applied Research in Dairy Industries
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Purpose/ to build clear perceptions about the level of the effects of organizational failures on the competitiveness of dairy factories and the role of dynamic knowledge capabilities in minimizing these impacts

Mythology/ Design approach Use deduction approach, the research was conducted in four dairy factories in Baghdad (Abu Ghraib, Agriculture, Halal and Ayon Al-Rafidain). It was applied to a sample of (155) individuals representing a sample of the research community from factory owners, managers, Engineers, technicians and experienced workers in the dairy industry. The questionnaire was used as a main tool for collecting data, information and statistical tools in the extraction, testing and analysis o

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Publication Date
Sun Jan 22 2023
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The impact of international Accounting Standard No (21) in reducing tax obstacles : applied research in the General Authority for Taxes .
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               The research aimed to shed light on the impact of international Accounting Standard No (21) on tax obstacles represented by (tax evasion, double taxation) The financial statements of a group of banks operating in the private sector were relied upon to know the impact of the standard on tax obstacles, as well as knowing the amount of amounts, The researcher relied on the method of financial analysis of that data, which was obtained from the website of the Securities Commission, and conducted personal interviews with a number of university professors, chartered accountants, financial experts, banks, and the General Authority for Taxes to benefit from their

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