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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
Thu Jun 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Use some of the scheduling rules for nursing staffs to improve operational performance _ Applied Research in al- Shahed al-Sadr General Hospital
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             Hospitals are part of the service organizations and most importantly at the level of individuals because they are tied to the people health and their daily lives , the nursing service is one of the important services provided by hospitals, and nurses are the human resource that offers this service, from this standpoint the idea of  ​​research came to prepare work Scheduling for nurses in a scientific way to improve performance operational for their services and provide efficient service available 24 hours a day, the research use one of the modern and scientific rules of scheduling its “schedule of

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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Experimental Study of the Effect of Condenser Tubes Distribution for Domestic Refrigerator
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The performance of a condenser in a domestic refrigerator system without wires and a condenser with a novel design consisted of number of loops as elliptical shape is investigated experimentally in this work. The experiment was conducted with a refrigerator designed to work with HFC134a, under no load and with loads of (1.5,3 and 12 liters of water). In particular, the effects of shape change of the condenser were very important in heat transfer enhancement and reduce of the frictional loss as a result of reducing the pressure drop in the condenser. The results shown that compressor work decreases with elliptical condenser about (8.6% to 11.3%), and then the power consumption decreases also. The performance of household refrigerator with

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Publication Date
Sat Jan 07 2023
Journal Name
Journal Of Advanced Pharmacy Education And Research
Fimasartan attenuates edema and systemic changes in egg albumin-induced paw inflammation in rats
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Angiotensin receptor blockers are well known for their therapeutic efficacy and fimasartan has been used safely and efficiently since 2010 in the treatment of hypertension. The study aimed to examine the anti-inflammatory effect of fimasartan in egg albumin-induced inflammation in rats. Rats were treated with diclofenac (25 mg/kg, intraperitoneally) or fimasartan at two different doses (3 or 10 mg/kg, intraperitoneally). The increase in the thickness of the paw was considered to be edema, which was measured using a vernier caliper. Serum was collected to analyze the systemic production of the inflammatory mediators TNF-α, and IL-6. The results showed that fimasartan in both doses significantly reduced edema in inflamed rat paws and produce

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Publication Date
Wed Jun 30 2010
Journal Name
Al-kindy College Medical Journal
The Influences of Aminophylline and Indomethacin in Glycerol-Induced Acute Renal Failure in Rats
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Background: Adenosine mediates homodynamic
changes and resulted in the production of acute renal
failure (ARF) in female Albino-Wister rats, therefore,
adenosine level increases highly in ARF.
Objective: This experiment was designed to
investigate the effect of the adenosine antagonist
aminophylline and the adenosine agonist indomethacin on glycerol-induced ARF.
Method: Glycerol induced ARF was produced by a
single dose (10ml/kg, 50%v/v with distilled water i.m)
in rats, which were restricted to drinking water.
Aminophylline was used in our study in a dose of
25mg/kg, i.p) while the dose of indomethacin was
10mg/kg, i.p), assessment of renal function was done
by measuring blood urea
nitrogen (BUN

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Publication Date
Thu Sep 01 2016
Journal Name
Journal Of Engineering
The Effect of Vehicle Body Shapes on the Near Wake Region and Drag Coefficient: A Numerical Study
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The purpose of this paper is to gain a good understanding about wake region behind the car body due to the aerodynamic effect when the air flows over the road vehicle during its movement. The main goal of this study is to discuss the effect of the geometry on the wake region and the aerodynamic drag coefficient. Results will be achieved by using two different shapes, which are the fastback and the notchback. The study will be implemented by the Computational Fluid Dynamic (CFD) by using STAR-CCM+® software for the simulation. This study investigates the steady turbulent flow using k-epsilon turbulence model. The results obtained from the simulation show that the region of the air separation behind the vehicle

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Publication Date
Wed May 31 2017
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
THE EFFECT OF ALCOHOLIC EXTRACT OF ANETHUM GRAVEOLENS IN ALLOXAN INDUCED DIABETIC RATS.: THE EFFECT OF ALCOHOLIC EXTRACT OF ANETHUM GRAVEOLENS IN ALLOXAN INDUCED DIABETIC RATS.
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Active compounds were extracted from Anethum gravoelens to produce safety vegetable treat for diabetic, the results showed that alcoholic extract of Anethum gravoelens contain Alkaloid, glycosides, phenols, resins, saponins, coumarins, flavonoide, terpenes, steroids and volatile oils. after that it was studied the effect of alcoholic extract at dose 50, 100 mg/kg of body weight in reduced glucose level in serum of diabetic rats induced by alloxan, after the end of experiment for period 30 days the rats fasting 12 hours to measure the level of glucose in serum, the result showed asignificant decrease in serum glucose level of rats treated with extract in comparison with positive group (alloxan), So biochemical tests showed significant dec

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Publication Date
Fri Sep 15 2023
Journal Name
Journal Of Baghdad College Of Dentistry
Osseointegration effects of whey protein (histological and histomorphological observations): An experimental study on rabbits
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Background: Whey protein is the green-yellow colored, liquid portion of the milk, and it is also called the cheese serum, it is obtained after the separation of curd, during the coagulation of the milk. It contains a considerable amount of α-helix pattern with an evenly distributed hydrophobic and hydrophilic as well as basic and acidic amino acids along with their polypeptide chain. The major whey protein constituents include β-lactoglobulin (β-LG),α-lactalbumin (α-LA), immunoglobulins (IG), bovine serum albumin (BSA), bovine lactoperoxidase (LP), bovine lactoferrin (BLF) and minor amounts of a glycol macro peptide (GMP). Osseointegration can be defined as a process that is immune driven which leads to the formatio

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Publication Date
Thu Feb 28 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Use Of Artificial Neural Networks In Developing The Role Of Auditor In Discovering Fundamental Errors: An Applied Research In General Company for Electrical Industries and Nasr General Company for Mechanical Industries
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Artificial neural networks usage, as a developed technique, increased in many fields such as Auditing business. Contemporary auditor should cope with the challenges of the technology evolution in the business environment by using computerized techniques such as Artificial neural networks, This research is the first work made in the field of modern techniques of the artificial neural networks in the field of auditing; it is made by using thesample of neural networks as a sample of the artificial multi-layer Back Propagation neural networks in the field of detecting fundamental mistakes of the financial statements when making auditing. The research objectives at offering a methodology for the application of theartificial neural networks wi

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Publication Date
Mon Jan 28 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The role of audit committees in reducing the risk of external Auditors Engagement Regarding Accepting Assignment: An Applied research in a sample of Iraqi private banks And Audit Bureaus
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The research aims to identify the most important concerns that led to the increase of  interest in the topic of corporate governance and specifically highlighting  the role of the audit committees of the Administration  Board in reducing the risk of the auditor and the rationalization of professional judgments، in particular about accepting  the assignment and setting the fees of the audit process by extrapolating  global experience in this area ، and a field study is conducted for a sample of private Iraqi banks to evaluate the role of audit committees constituted currently per with bank law no. (94) of 2004 and to be acknowledged with actual performance of these committees and their role in recommending the n

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Publication Date
Sun Sep 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Investment portfolio risks of the insurance company and their impacts on profitability ratios: An applied research at the national insurance co. for the period 2004-2014
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The research is trying to identify the investment portfolio risks of the insurance company and their impact, on the Profitability ratios of the company, and whether the company's scientific methods followed in the measurement of these risks, and conducted research in the National Insurance Company. by relying on its annual budget as well as the annual reports, The search dealing with these data in theoretical and practical major premise to statistically significant between to investment portfolio risk and financial performance correlation and reach a set of conclusions and recommendations which are the following.                

investments include many ri

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