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.
Whatever forms embodied in nature or in the product by forming elements, Kahadjom, fonts, and colors that characterized that her aesthetic and expressive values evoked to multiple indications of which are unequivocal, including what is iconic. Each one of these constituent elements of her form of extreme importance
Israel is one of the countries most interested in Iran's nuclear program file, and the progress of negotiations between Iran and the six countries and will end it, as well as the nature of the relationship between Iran and the United States of America. Is determined by the Israeli vision of the nature of Iran's nuclear program Iran's policy toward Israel orientations, which does not recognize the existence of Israel. Israel, therefore, one of the countries pushing to prevent Iran from acquiring nuclear technology. However, those Israeli efforts did not succeed in achieving its objectives, the United States of America and European countries is well aware of the risk of stenosis on Iran, as well as the risks and the consequences of militar
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A man find himself in front of narrative literal productions when he read the title of this paper that deals with specialist , followers of Arabic literal narration productions through the era of Arabic literature in a period arrived to 1500 years. It is strange to present (Narration art in Arabic heritage) , in addition to (Arabic diwan) . This matter introduces us to come back to the past to inspect Arabic narration production , specially that is called (Artistic narration ) which is full ,variety of purposes and goals.
The current study deals with the Islamic Arab of Mongolian invasion in the Island of Euphrates. We have exposed conditions of Levant before the Mongolian invasion and that includes situations of princess of Levant and their caliphates , they have been unaware the danger surrounding them and their country. It has also included the Islamic Arabic threat through the integration of Islamic Arabic cities residents in Levant to confront
This study deals with it the era of Taher Bin Al Hussein for his son Abdullah when preside Diyarbakir and Rabia in succession of ALMa`amoon Abbasi in the political and historical dimensions
تواجه المجتمعات مشكلات متعددة أجتماعية وأقتصادية وثقافية تنعكس على التعليم فتزيد من مشكلاته و خاصة في عصر يتزايد فيه عدد السكان وبالمقابل يتزايد الطلب على التعليم ، لذلك يصبح التخطيط التربوي ضرورة ملحة للدول النامية أذ أن قطاع التربية والتعليم يعد من أهم قطاعات التنمية في تلك الدول ,ولكي تستطيع التربية أن تسهم في قطاعات التنمية قي تلك الدول الشاملة يجب أن تتصف بالجودة في كل عناصرها ومكوناتها وان
... Show Moreانصبت هذه الدراسة على قياس جودة الخدمة، وبوجه خاص ماهية أبعاد جودة الخدمة التي يجري قياسها للوصول إلى مستوى جودة الخدمة. وتم التطبيق على خدمة التعليم العالي الخاص، حيث جرى اختيار عينة من طلبة جامعة خاصة لتعبئة الاستبانة الخاصة بالدراسة. وكان هناك 360استبانة تم تحليل البيانات فيها من خلال مؤشرات الإحصاء الوصفي، وتحليل الارتباط، وتحليل الانحدار المتعدد. وقد توصلت الدراسة إلى وجود علاقة ارتباط بين مستويات
... Show Moreتعد الجامعات من أهم المؤسسات المجتمعية التي تؤثر وتتأثر بالجو الاجتماعي المحيط بها، فهي من صنع المجتمع من ناحية، ومن ناحية أخرى هي أداته في صنع قياداته السياسية، الفكرية، الفنية، والمهنية، ومن هنا كان لكل جامعة رسالتها التي تتولى تحقيقها، فالجامعة في القرن العشرين تختلف رسالتها وغايتها عن الجامعة في القرن الحادي والعشرين. ولكي تقوم الجامعة بدور أفضل في خدمة المجتمع وتحمل المسؤولية المجتمعية فلابد لها من وض
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