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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
Mon Jun 15 2020
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of diabetes mellitus on periodontal health status, salivary flow rate and salivary pH in patients with chronic periodontitis
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Background: Diabetes and periodontitis are considered as chronic diseases with a bidirectional relationship between them. This study aimed to determine and compare the severity of periodontal health status and salivary parameters in diabetic and non-diabetic patients with chronic periodontitis. Materials and Methods: Seventy participants were enrolled in this study. The subjects were divided into three groups: Group I: 25 patients had type 2 diabetes mellitus with chronic periodontitis, Group 2: 25 patients had chronic periodontitis and with no history of any systemic diseases, Group 3: 20 subjects had healthy periodontium and were systemically healthy. Unstimulated whole saliva was collected for measurement of salivary flow rate and pH.

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Publication Date
Thu Jun 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
The role of loyal workers enhance market share center the human resource management strategies / field research in cellular telecommunication companies
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The problem for the search to identify the role of loyal workers through (emotional loyalty, moral loyalty, continued loyalty) in enhancing the market share of the corporate center the human resource management strategies, namely (selection, training and development, and performance evaluation, and returns the system) for the parent company of cellular Allotsalat in Baghdad ,, and show the importance of research through the benefit to the company, through the importance of the search results, it draws the attention of decision-makers and those in charge of managing these human resources on the importance of those resources and work to develop them and keep them in order to increase their loyalty towards their organization and the

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Publication Date
Wed Sep 30 2020
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Experimental Study for Assessment of Cutting Density Effect on Hole Cleaning Efficiency in Inclined and Horizontal Wells
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The poor hole cleaning efficiency could causes many problems such as high torque, drag, poor hydraulics and pipe stuck. These inherent problems result in an avoidable high operation cost which this study tried to address.  In this study, the effect of cutting density on hole cleaning efficiency in deviated and horizontal wells was investigated. Experiments were conducted using 40 feet (12 m) long of flow loop made from iron and PVC. However, the test section was made from PVC with (5.1m) long and (4” ID) for outer pipe and (2” OD) inner pipe. The cutting transport ratio (CTR) was determined from weight measurements for each test. Cutting Transport Ratio has been investigated for effects of the following parameters; flow rate, cu

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Publication Date
Sun Dec 27 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The use of electronic applications in the preparation of operational budgets: An applied research in one of the private sector companies for dairy industry / Baghdad
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A revolution called information revolution has recently invaded the world. It is Currently considered one of the most important properties of development to the countries of the world The criteria provided by computers such as accuracy, speed, time saving Storage and restore have led them to be widely used in economy, industry, agriculture, communications, etc., as well as being the major finder of reengineering the operations of innovation. The use of computers in the preparation of budgets will lead to achieve accuracy. Since, the operation draws upon the statistic and quantity estimations about budget items, the computerized balance sheet may save time and effort of preparing mathematical equations annually. According to the problem o

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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The extent of the industrial company's response to blue market strategy indicators: Applied research
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The current research aims to describe the level of responsiveness and awareness of the officials of the General Company for Construction Industries to the indicators of the blue market strategy of (1. reduction 2. exclusion 3. increase 4. innovation) and the degree of prioritization according to their importance as well as the differences in the responses of the sample investigated according to the personal variables. As a main tool in the collection of data from the sample, which consisted of(34) officers (Associate, Manager, Section Manager, Division Officer) in the company being investigated, and computed mean, standard deviations, percentage weights,and test (x2 )  based on the SPSS. The research reached the following

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Publication Date
Tue Sep 01 2015
Journal Name
2015 7th Computer Science And Electronic Engineering Conference (ceec)
An experimental investigation on PCA based on cosine similarity and correlation for text feature dimensionality reduction
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Publication Date
Mon Nov 01 2021
Journal Name
Journal Of Engineering
Numerical Study for the Tube Rotation Effect on Melting Process in Shell and Tube Latent Heat Energy Storage LHES System
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Although renewable energy systems have become an interesting global issue, it is not continuous either daily or seasonally. Latent heat energy storage (LHES) is one of the suitable solutions for this problem. LHES becomes a basic element in renewable energy systems. LHES compensate for the energy lack when these systems are at low production conditions. The present work considered a shell and tube LHES for numerical investigation of the tube rotation influence on the melting process. The simulation and calculations were carried out using ANSYS Fluent software. Paraffin wax represents the phase change material (PCM) in this work, while water was selected to be the heat transfer fluid (HTF). The calculations were carried o

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Publication Date
Wed Oct 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
knowledge strategic abilities And impact in the building of competitive advantage Field research the views of a sample of the administrative leaders of the Iraqi private banks
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The research synthesis variables of competitive advantage and the mechanism achieved by focusing on knowledge abilities and strategic of the administrative leadership, and governments and the developed countries took the racing frantically and my destiny to invest more money and resources to development of wealth and human knowledge is so choice investment winner always and who Aaikhyee never, because God Almighty give humans the abilities of all other creatures and that these abilities varying from person to person, there is the problem of search provoking questions about the essence of what it's about research and both sides theoretical and field, the objective of this research

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Publication Date
Wed Oct 31 2018
Journal Name
Heat Transfer-asian Research
Comparative study on heat transfer enhancement of nanofluids flow in ribs tube using CFD simulation
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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Vibration Analysis of Cross-Ply Plates Under Initial Stress Using Refined Theory
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Natural frequency under initial stresses for simply supported cross-ply composite laminated plates (E glass- fiber) are obtained using Refind theory (RPT). This theory accounts for parabolic distribution of the transverse shear strain through the plate thickness and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. The governing equations for Eigen value problem under initial stress are derived using Hamilton’s principle and solved using Navier solution for simply supported cross-ply symmetric and antisymmetric laminated plates. The effect of many design factors such as modulus ratio, thickness ratio and number of laminates on the Natural frequency and buckling stresses

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