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Investigation of R134a Flow Boiling Heat Transfer and Pressure Drop in the Evaporator Test Section of Refrigeration System
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This paper presents an experimental and theoretical analysis to investigate the two-phase flow boiling heat transfer coefficient and pressure drop of the refrigerant R-134a in the evaporator test section of the refrigeration system under different operating conditions. The test conditions considered are, for heat flux (13.7-36.6) kW/m2, mass flux (52-105) kg/m2.s, vapor quality (0.2-1) and saturation temperature (-15 to -3.7) ˚C. Experiments were carried out using a test rig for a 310W capacity refrigeration system, which is designed and constructed in the current work. Investigating of the experimental results has revealed that, the enhancement in local heat transfer coefficient for relatively higher heat flux 36.6 kW/m2 was about 38% compared to 13.7 kW/m2 at constant operating conditions. The enhancement in heat transfer coefficient was about 57% when the mass flux increased from 52 kg/m2.s to 105 kg/m2.s at constant test conditions. The enhancement in the heat transfer coefficient was about 64% when the saturation temperature increased from -8 to -3.7 at fixed refrigerant mass velocity and heat flux. The effect of mass velocity on pressure drop was relatively higher by about 27% than that for heat flux at specified test conditions. The comparison between the experimental and theoretical results has shown an acceptable agreement with an average deviation of 21%.

 

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
the administrative investigation and its impact on the performance of the offices of the inspectors General.
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The purpose of this research is to highlight the relationship between the   administrative investigation and the improvement of institutional performance, and the research sought to achieve a set of cognitive and applied goals. the administrative investigation is the modern trend of managing the offices of the general  hginspectors and the main source to build the necessary standards to manage and invest its resources efficiently and effectively required to achieve the goals it seeks. The institutional performance is the cornerstone for the implementation of all tasks and duties carried out by institutions operating within the borders of a particular country, The significant change

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Publication Date
Wed Jul 31 2024
Journal Name
Iraqi Geological Journal
Correlating Capillary Pressure and Resistivity Index for Carbonate Reservoir
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Capillary pressure is a significant parameter in characterizing and modeling petroleum reservoirs. However, costly laboratory measurements may not be sufficiently available in some cases. The problem amplifies for carbonate reservoirs because relatively enormous capillary pressure curves are required for reservoir study due to heterogeneity. In this work, the laboratory measurements of capillary pressure and formation resistivity index were correlated as both parameters are functions of saturation. Forty-one core samples from an Iraqi carbonate reservoir were used to develop the correlation according to the hydraulic flow units concept. Flow zone indicator (FZI) and Pore Geometry and Structure (PGS) approaches were used to identify

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Publication Date
Wed Jul 31 2024
Journal Name
Iraqi Geological Journal
Correlating Capillary Pressure and Resistivity Index for Carbonate Reservoir
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Capillary pressure is a significant parameter in characterizing and modeling petroleum reservoirs. However, costly laboratory measurements may not be sufficiently available in some cases. The problem amplifies for carbonate reservoirs because relatively enormous capillary pressure curves are required for reservoir study due to heterogeneity. In this work, the laboratory measurements of capillary pressure and formation resistivity index were correlated as both parameters are functions of saturation. Forty-one core samples from an Iraqi carbonate reservoir were used to develop the correlation according to the hydraulic flow units concept. Flow zone indicator (FZI) and Pore Geometry and Structure (PGS) approaches were used to identify

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Publication Date
Wed Jun 29 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Determining Optimum Oil Separator Size and Optimum Operating Pressure
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The optimum separators operating pressure is determined by using flash calculations and equilibrium ratios. In this study, the optimum separator size for Jambur field is calculated by using equations introduced by Arnold and Stewart and API12J Specification [1]. Because Jambur field has a high production rate two conditions are taken in the study to determine separator size, first based on production rate 80,000 bbl/day and second based on split the production between two banks A and B (40,000 bbl/day for each bank). The calculation resulted in optimum separator pressure for the first stage of 700 psi, and the second stage of 300 psi, and the third stage of 120 psi. The results show that as the number of stages increased above three-stag

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Crossref
Publication Date
Wed Jun 29 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Determining Optimum Oil Separator Size and Optimum Operating Pressure
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The optimum separators operating pressure is determined by using flash calculations and equilibrium ratios. In this study, the optimum separator size for Jambur field is calculated by using equations introduced by Arnold and Stewart and API12J Specification [1]. Because Jambur field has a high production rate two conditions are taken in the study to determine separator size, first based on production rate 80,000 bbl/day and second based on split the production between two banks A and B (40,000 bbl/day for each bank). The calculation resulted in optimum separator pressure for the first stage of 700 psi, and the second stage of 300 psi, and the third stage of 120 psi. The results show that as the number of stages increased above three

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Publication Date
Fri Feb 01 2019
Journal Name
Indian Journal Of Natural Sciences
Design and Test of Electrochemistry of Electrodes Catalysis for an Alkaline Fuel Cell
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Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
International variables and their impact on the flow of foreign direct investment in Gulf Cooperation Council (GCC)
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Abstract:

The six Arab Gulf states (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, UAE) play a vital role, especially with its geographical location and natural  resources (oil and gas) as well as other cultural and civilizational elements, in achieving  global economic balance and more specifically global energy security, naturally  because of  these countries have a comparative advantage in the field of fossil energy (oil and gas), thus this sector becomes more attractive for local and international investments alike. Being  the energy sector a leader sector in the economic development process, and the basic factor to achieve savings and financial surpluses in thes

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Publication Date
Wed Jan 23 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The importance of cash flow statement in reducing credit risk and liquidity: بحث تطبيقي في مصرف الرشيد
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Banks face different types of banking risks that limit the performance of its functions and achieve its objectives, including the financial risk that is based on current research into two types including a credit and liquidity risks. And established credit risk due to the possibility of delaying the borrowers to fulfill their obligations to the bank when due or non-payments on according to the terms agreed upon, while liquidity risk arises as a result of the inability of the bank to fund the financial needs, any inability to provide cash to pay its obligations short on credit without achieving tangible loss or the inability to employ the funds properly and show the liquidity risk in the event of inadequate cash inflows to the bank for an

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Publication Date
Tue Feb 05 2019
Journal Name
Journal Of The College Of Education For Women
System of governance and administration in the state of the Ottoman Algeria (1518-1830)
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Algeria is one of the states that are important to the Ottoman state, because of its geographic location is important to the Mediterranean Sea, as well as the economic resources of the nature of its soil geography and climate,diverse, making it the focus of attention of the Ottomans, along with the van, which has increased the interest of the Ottomans in Algeriais the fall Andalusat the hands of the Spaniardsin1492, and force the Muslims to get out of them, and did not Only Europeans do it, butrushed to the prosecution of Muslims tothe coast of North Africa and seizing control of manyofits ports and cities, prompting the Ottoman state to go forth and back to the barn Muslims,Especially after hehad appealed to the Arabs of the Ottoman sta

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Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
The Effective of Pressure and Sintering Temperature for Hardness Characteristics of Shape Memory Alloy by Using Taguchi Technique
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This paper presents the Taguchi approach for optimization of hardness for  shape memory alloy (Cu-Al-Ni) . The influence of  powder metallurgy parameters on hardness has been investigated. Taguchi technique and ANOVA were used for analysis. Nine experimental runs based on Taguchi’s L9 orthogonal array were performed (OA),for two parameters was study (Pressure and sintering temperature) for three different levels (300 ,500 and 700) MPa ,(700 ,800 and  900)oC respectively . Main effect, signal-to-noise (S/N) ratio was study, and analysis of variance (ANOVA) using  to investigate the micro-hardness characteristics of the shape memory alloy .after application the result of study shown the hei

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