The present study involves experimental analysis of the modified Closed Wet Cooling Tower (CWCT) based on first and second law of thermodynamics, to gain a deeper knowledge in this important field of engineering in Iraq. For this purpose, a prototype of CWCT optimized by added packing under a heat exchanger 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 towers thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of air measured at intermediate points of the heat exchanger and packing. Exergy of water and air were calculated by applying the exergy destruction method on the cooling tower. Experimental results showed a significant performance improvement when using packing on the CWCT. It can be observed that the thermal efficiency for the CWCT with packing under a heat exchanger and CWCT with packing above the heat exchanger are approximately 40% and 25% higher than that of the CWCT without packing respectively. As another part of the experiment results, it is indicated that the exergy destruction is directly proportional to air flow rate, cooling water flow rate, inlet cooling water flow rate and inlet Air Wet Bulb Temperature (AWBT) whereas, it is inversely proportional with spray water flow rate. In comparison with the cooling capacity of the tower, it was found that the exergy destruction approximately less than 20%. Exergy efficiency behavior is inversely proportional with the behavior of the exergy destruction. Empirical correlations are obtained to predict water film heat transfer coefficient and air-water mass transfer coefficient considering the influences of operational parameters.
The research aims to demonstrate the impact of tax techniques on the quality of services provided to income taxpayers by studying the correlational and influencing relationships between the exploited variable (tax techniques) and the dependent variable (the quality of services provided to income taxpayers), and in line with the research objectives, the main hypothesis of the research was formulated (there is a relationship Significance between tax techniques and the quality of services provided to income taxpayers) a number of sub-hypotheses emerged from this hypothesis that were stated in the research methodology, and a number of conclusions were reached, the most important of which were (through the use of the correlation coeff
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This research aims to compare Bayesian Method and Full Maximum Likelihood to estimate hierarchical Poisson regression model.
The comparison was done by simulation using different sample sizes (n = 30, 60, 120) and different Frequencies (r = 1000, 5000) for the experiments as was the adoption of the Mean Square Error to compare the preference estimation methods and then choose the best way to appreciate model and concluded that hierarchical Poisson regression model that has been appreciated Full Maximum Likelihood Full Maximum Likelihood with sample size (n = 30) is the best to represent the maternal mortality data after it has been reliance value param
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The main target of this research is to follow the stages of the emergence of
the idea of republican form of government from its very beginning , yet there
were many elements from different estates thinker , educated , few of heads of
clans . This first opportunity for the mobilization of politically-minded people
with fundamental activity like najei shokat . hussain al-rahal notable poet maruf
al-rasafi those who formed what so called the political elite who believed in
constitutional , democratic parliamentary republic , one of them was al-rahal who
called for a constitutional republic even before the emergence of the
constitutional movement in Iran and ottoman empire (1908).
The holy najaf become cultural cen
The study present a detailed description of the new violent situation that those women faced after 2003 in Iraqi society and the effect of such violence and security breaking down on minority women perception and feeling of bonding or adaptation with this society and how they look to the aaceptance of the society to them and their minority group as a whole. In addition to the impact of these social changes after 2003,on the women rights and personal freedom. One of the aims of the study is to provide data base to be used when efforts present to put a policies or programs for supporting the minority women. Another aim is to point out and define the violations commited on the rights of those women. The field survey included 2100 women from
... Show MoreThe organization and development of the irrigation system and agrarian reform in Iraq had an impact on the diversity of its methods and uses.
The organization and development of the irrigation system and agrarian reform in Iraq had an impact on the diversity of its methods and uses
The legal text in the language of civil law, constitutional law, language of judges, and legal profession is concerned with a legal language and words that are coherently significant
العلوم السياسية في العراق بداياتها ، نشأتها ، تطورها ، ومفرداتها التدريسية
العراق في مواجهة متطلبات الانضمام الى منظمة التجارة العالمية
ملامح من فكرة القانون الطبيعي في حضارة العراق القديم