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Thermal Characteristics of Closed Wet Cooling Tower Using Different Heat Exchanger Tubes Arrangement
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This paper presents thermal characteristics analysis of a modified Closed Wet Cooling Tower (CWCT) based on heat and mass transfer principles to improve the performance of this tower in Iraq. A prototype of CWCT optimized by added packing was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of the air measured at intermediate points of the heat exchanger and packing. Heat exchangers consist of four rows and eight columns for an inline tubes arrangement and six rows and five columns for staggered tubes arrangement. According to experimental data, the inline tubes arrangement has a better thermal performance than the staggered tubes arrangement. The inline tubes arrangement enhanced thermal efficiency more than (7%) compared to the staggered tubes arrangement. Furthermore the effect of added packing to CWCT on thermal performance was significant compared to CWCT without packing. Comparing CWCT with packing, it has been observed that the best performance for the CWCT with packing under heat exchanger. It can be watched that the thermal efficiency for CWCT with packing under heat exchanger and CWCT with packing above heat exchanger approximately (28%) and (16%) higher than that CWCT without packing respectively. This study provides correlations to predict heat and mass transfer considering the influences of operational parameters for both inline and staggered heat exchanger tubes arrangement.

 

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of The College Of Languages (jcl)
Assess the level of achievement
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This work, in fact, is an English language teaching study (henceforth, ELT) which may provide the inspiration for much –needed research on issues such as testing students' level of achievement in articulatory phonetics at the university level. It attempts to answer two questions: 1)What is college students' level of achievement in articulatory phonetics? 2- Are there any statistical significant differences in the achievement of college students in articulatory phonetics between the production and recognition testing techniques? This research falls into three sections: Section one indicates the problem, the aims, the hypotheses, the procedures, the limits and the value of the study. Section two provides a general overview of the articul

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Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Educational And Psychological Researches
Educational goals of Quranic proverbs
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The research sought to know the educational goals of Quranic proverbs, The first chapter: includes general terms of research, its problem, its importance, its objectives, its methodology, and the definition of terms. In the second chapter: Proverbs in Quranic usage such as simple and complex proverbs, standard proverbs, In the third chapter, the educational objectives of the Quranic proverbs include: bringing the meaning, persuasion, thought provoking ..... the educational characteristics of the Koranic verses, including: accuracy of photography, and the truth of similar, and included the lesson applied lesson, Chapter fourth : Conclusions and Recommendations with abstra

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Publication Date
Fri Oct 16 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Frictional resistance of aesthetic brackets
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Background: The aim of this study was to evaluate and compare the static frictional forces produced by monocrystalline ceramic (sapphire) bracket and polycrystalline ceramic bracket. Materials and methods: one hindered twenty brackets/segment of archwire combinations were used, each bracket/segment of archwire combination was tested 10 times. The tests were performed in a universal testing Instron machine. The data was submitted to in depended t-test. Results: The independent sample t-tests showed a highly significant difference in the static frictional forces between monocrystalline ceramic (sapphire) bracket and polycrystalline ceramic bracket. Conclusion: According to the biomechanical result gained from the present study, the monocryst

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Publication Date
Sun Mar 19 2023
Journal Name
Journal Of Educational And Psychological Researches
Communicative Competence of University Students
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Abstract

The current research aims to identify the communicative competence of university students, to identify the levels of communicative competence among university students and which of these levels are more common, and to identify the significance of differences in communicative competence among university students according to the variables of gender and specialization. The study population consisted of (782) male and female students, as the statistical analysis sample was limited to (400) male and female students to extract the psychometric properties of the current research tool. The study sample included (382) male and female students at the University of Baghdad who were chosen by the stratified random

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Publication Date
Fri Oct 16 2026
Journal Name
Defense University Journal
Military expenditures of the Umayyadstate
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Publication Date
Thu Apr 11 2019
Journal Name
Political Sciences Journal
Scientific Activities College of branches
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Scientific Activities College of branches

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Publication Date
Wed May 01 2019
Journal Name
Journal Of Engineering
Thixotropic Hardening of Fao Clay
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Fao region is characterized by weak soft silty clay to clayey silt thick layer which extends to a depth of about 20 m. The construction of some structures on such soils may needs piles. During the installation of driven piles, the soil geotechnical properties are exposed to significant changes result due to shearing under large shear strains. These changes significantly decrease the shear strength of the virgin soil due to the destruction of soil structure caused by remolding. The degradation of shear strength is usually followed by strength regaining which is called “Thixotropy”. In this study, the thixotropic effect on Fao clay was investigated. Many disturbed and undisturbed soil samples were brought from Fao regi

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Publication Date
Sun Dec 31 2000
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Transient Behavior of Straight Fins
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Publication Date
Mon Jun 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Economic Implications of Economic Corruption
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There are  many  economic issues that  concern society at the local and international levels and which constitute  a serious  challenge to the societies  and governments , perhaps  including  the issue of corruption  in all its  forms and manifestations and effects , which  now attract the attention  the issue of human society everywhere .                                                      

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Crossref (1)
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Publication Date
Fri Mar 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Scale-Up of Eelectrochemical Reactors
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