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.
Day after day, Morsek literature 879-1018/1492-1609proves the completion of all literary branches starting from poetry with its different purposes to include prose with its various subjects. In 2016, a complete text of ‘the literature of Morsek journey
Day after day, Morsek literature 879-1018/1492-1609proves the completion of all literary branches starting from poetry with its different purposes to include prose with its various subjects. In 2016, a complete text of ‘the literature of Morsek journeys
استهدف البحث الكشف عن المكانة الاجتماعية لطفل الروضة بين أقرانه ، ودلالة الفروق في المكانة الاجتماعية لاطفال عينة البحث التي تعزي الى بعض المتغيرات من خلال الاجابة عن الاسئلة الاتية :
اولاً : ما المكانة الاجتماعية لدى اطفال الروضة بين اقرانهم ؟
ثانياً : ما علاقة المكانة الاجتماعية لدى اطفال الروضة ببعض المتغيرات و ذلك من خلال اختبار الفرضيات الصفرية الآتية :
يمر عالمنا المعاصر اليوم بمرحلة من التطور والتغيير السريعين لم يسبق له أن مر بهما فـي تاريخ البشرية ، ويشمل مظاهر الحياة الأنسانية والأقتصادية والعلمية والتربويـة والنفسية وغير ذلك . وتختلف سرعة هذا التغيير من مجتمع الـى مجتمع آخر , وأدى هذا الى تراكم كميات كبيرة من المعلومات .
لقد أكد الكثير مـن التربويين أن التطور التكنولوجي فـي ال
... Show MoreThe thesis discusses the concept of the new international regionalism that emerged after the growing effects and repercussions of globalization with its economic, political and security dimensions after the end of the Cold War and the crystallization of a different international system dominated by the United States of America, so that the major countries and actors in the international system realize the danger of globalization and move towards adopting regional arrangements to contain the negative effects of globalization. The Asia-Pacific model was chosen as a model for the study.
المستخلص: يهدف البحث الى التعرف على بقاء اثر المعلومة عن طريق الاجابة عن السؤال: ما مدى بقاء اثر التعلم بين التعليم الالكتروني والتعليم االحضوري ؟ تم تطبيق البحث في العام الدراسي( 2020-2021 م) في العراق. تم استخدام المنهج الوصفي بالاسلوب المقارن في عقد مقارنة بين التعليم الالكتروني والتعليم الحضوري. وكان مجتمع البحث من طلبة المرحلة الرابعة كلية التربية للعلوم الصرفة – ابن الهيثم ,و العيتة من قسم الرياضيات الم
... Show Moreه رثا قيقحتلو ،ةيبساحملا تامولعملا ةميق ةمئلام يف قيقدتلا ةنجلل ةيبساحملاو ةيلاملا ةربخلاو ةيللاقتسلاا ثحبلا تايضرف رابتخلا ةمزلالا تانايبلا عمجل ةنابتسا ةرامتسا مادختساب ةثحابلا تماق ةساردلا فده ةللاد وذ رثأ دجوي(يهو ةيبساحملاو ةيلاملا ةربخلل ةيئاصحإ ةللاد وذ رثا دجوي( ، )ةيبساحملا تامولعملا ةميق ةمئلام ىلع قيقدتلا ةنجل ةيللاقتسلا ةيئاصحا )ةيبساحملا تامولعملا ةميق ةمئلام ىلع ( نم تنوكت ةنيع ىلع تعزو ث
... Show MoreThe Andalusi did not leave any poetic art without expressing his psychological and sentimental emotions and the depth of emotions and it sincerity. We found Andalusian translated his emotions into poetry and in many different subjects