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.
أهمية الدراسة والحاجة اليها:
يعد النشاط المدرسي للمعلم والطالب جهدا عقلياً وبدنياً يبذله المعلم والطالب بمساعدة المدرسة لتحقيق اهداف مرسومة وهو ممارسة تظهر في اداء الطلبة على المستوى الحركي والفعلي والنفسي والاجتماعي بفعالية داخل المدرسة وخارجها. (اللقاني،بلا، ص82).
ان الانشطة والبرامج المدرسية التي تنظم داخل الصف
... Show Moreحل الاشكالية المنهجية في العلوم الانسانية المنهج البنيوي انموذجاً مقترحاً
The object of this study is to establish a global model to use of DeNovo programming the strategies of multi-Decision making process in the city of Baghdad.
Thus, we have chosen an important and an effective subject in the life of the citizen due to the importance of this subject in the Iraqi citizen of luck of water and for many reasons.
In this thesis, we have tackled the establishment of a global model to be able to reach solution or an alternative model a money the available alternative.
The alternative proposed here utilizes the application of the (DeNovo) programming approach suggested by (1982) in solving t
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That analytical procedures are of analytical tools important because it gives assurance to the auditor-free financial statements of the economic units replace the audit of cases offraud and errors and distortions, and thereby to increase the effectiveness of the audit process and confirm the possibility oftrust and reliance on the financial statements that Adfgaha auditor.
Inspite of identify evidence of proof necessary to enhance the auditor's opinion the results reached in the audit p
It was a women's importance in ancient societies، especially Mesopotamia as they worship mother goddess first entrance religious belief، which is undoubtedly a reflection of the vision of the community it represents the natural fertility cycle and Ishtar but realistic image of women dual and contradictory and nature of the code it by a thin love compassionate and another treachery and betrayal side and hatred. As we have seen in the Epic of Gilgamesh
The wisdom of the Creator ensures the call of every prophet with a miracle that would be something beyond what is familiar from the customs.the prophet Mohammad (pbuh)whose miracle was the Qur’an in a clear Arabic tongue
Find spins educational thought in the arguments of Imam Jafar Sadiq ( peace be upon him ), which is a valid approach to every age and generation , a fact the Lord's suitable for all ages, and a natural extension of the message the sky . Here was a project of Imam Sadiq ( peace be upon him ) for the breeding of individuals and the Islamic nation in general, so it was launched search to explain features of this educational thought when Imam Jafar Sadiq ( peace be upon him )
تولي المجتمعات المتقدمة اجتماعياً واقتصاديا وثقافيا وعلميا اهتماما بارزا للعنصر البشري واستثماره على أفضل صورة ممكنة لتحقيق التقدم والرفاهية لتلك المجتمعات وللأفراد على حد سواء , وتحتل تنمية الثروة العقلية واستثمارها محل الصدارة حيث يبذل اهتمام خاص للكشف عن المواهب والكفاءات المبدعة وتنميتها وتوجيهها ورعايتها علميا وتربويا ومهنيا وذلك لان العنصر البشري يعد جزءا لا يتجزأ من الثروة القومية للأمة حيث
... Show MoreGraph is a tool that can be used to simplify and solve network problems. Domination is a typical network problem that graph theory is well suited for. A subset of nodes in any network is called dominating if every node is contained in this subset, or is connected to a node in it via an edge. Because of the importance of domination in different areas, variant types of domination have been introduced according to the purpose they are used for. In this paper, two domination parameters the first is the restrained and the second is secure domination have been chosn. The secure domination, and some types of restrained domination in one type of trees is called complete ary tree are determined.
(19)
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In the past, an absolute authority was held by the father and his decisions were imposed
and obeyed strictly without discussion. Later, many economical changes took place and
affected all of the family members dramatically creating a whole new concept of authority
in the family, a one that is based upon sound leadership, mutual understanding and
consultation among family members.
Women carried responsibility of doing all domestic jobs and served family members,
however, when she went to work outside her house, these loads began disturbing and
exhausting her. Therefore, man started to participate in assisting his wife. In addition,
industrial advances contributed in making these jobs easier than before.
This has