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 essential objective of this study presents a analyzes of the combination of reality and fantasy in three dramas of Spanish author Alejandro Casona. "Trees die standing" (premiered in Buenos Aires in 1949), “Prohibited suicide in spring” (premiered in Mexico in 1937) and "The boat without fisherman" (premiered in Buenos Aires in 1945).
The first part is an introduction about the biography of Spanish author Alejandro Casona that will allow us to understand some peculiarities of his work in relation to the social historical context of his time.
In the second part of this study we have analyzed elements of reality and fantasy in the th
... Show MoreAL Sheikh Abdul Qadir Al Gilani is one of the famous Mysticists (sufi). He was known in his literary eloquent and rhetoric speeches. These speeches was cover both the poetry and prose. Also it was in the fields of preaching, soliloquy and maqamat.
دور وزارة الخارجية الامريكية في عملية صنع القرار
ليست الادارة المحلية أو نظام الحكم المحلي ابتكاراُ حديثاً للانسان، بل أنه لازم البشرية منذ أقدم العصور وحتى الآن، إذ الملاجظ أن القرى الصغيرة نشأت قبل أن تنشئ الدولة أو قيل أن يتبلور مفهوم الدولة في الوقت الحاضر وكانت القرى والمدن تجتمع بين حين وأخر- اجتماع أفرادها- لادارة شؤونهم وحل مشاكلهم، وكان هذا خير دليل لتطبيق مفهوم الديمقراطية المباشرة بين أفراد المجتمع الواحد، ولذلك فإن الحك
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مشكلة البحث:- تواجه المجتمعات العربية في المرحلة الراهنة ,تحديات كبيرة تستهدف الشاب العربي ،والتأثير عليه في الجوانب الاجتماعية والتربوية والثقافية والاقتصادية والأمنية والسياسية ولغض تسليط الأضواء على هذه الجوانب ولاسيما الجانب الاجتماعي،من هنا تبرز مشكلة البحث الحالي في التعرف على توقعات الشباب العربي لمشكلاتهم الاجتماعية في المرحلة الراهنة .
أهمية البحث:-
... Show MoreLiterary heritage and its employment in poetry has received the attention of poets, and they have employed it in their literary texts, as this employment is one of the oldest phenomena in Arabic literature, that the inspiration of this heritage in texts through the overlap of their texts with previous texts, and no poet neglected the importance of this employment. The ancient critics determined that the poet’s special culture is represented in the necessity of taking from the ancients, and this taking is the reference from which the poet draws his material and idea, as well as to clarify the meaning and its significance
يهدف هذا البحث الموسوم بـ (المنهج النقدي في كتاب الرجال للنجاشي(ت 450هـ )إلى تسليط الضوء على حياة النجاشي ومكانته العلمية والكشف عن منهجه النقدي في كتابه المذكور.
من المتفق عليه أن هناك طريقا واحدا لنشر الثقافة والقضاء على الجهل هو التعليم .ولعل أبرز ماشهدته مدينة بغداد من تطور هو ظهور المدر سة ومن ثم إنتشارها بشكل كبير وفق المفهوم الحديث مما أثرفي عموم الحياة اليومية ، ومن ضمنها التعليم العالي .إن الإستقرار من أهم ماتحتاجه الجامعة للقيام بواجباتها ولايأتي الإستقرار إلا بالإستقرار الذي يضمن لنا أن تكون الجامعة بعيدة عن ما قد يستجد من الأهواء و النزاعات.
It is an analytical study carried out at university of Basra using a sample included the dean ,assistants and managers of scientific dept. in the university for about(63)managers .The study aimed at discovering a model of crises management in the university.The researcher adopted the descriptive survey methodology.To achieve the objective of the study ,a questionnaire of (41)statements was developed covering five main variables like ,signal detection, prevention and preparedness, response, recovery and learning .The validity of the questionnaire was done by a group of referees .Its stability was determined by Cronbach,s Alfa .The questionnair,s stability coefficient was(0.
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There are many researches deals with constructing an efficient solutions for real problem having Multi - objective confronted with each others. In this paper we construct a decision for Multi – objectives based on building a mathematical model formulating a unique objective function by combining the confronted objectives functions. Also we are presented some theories concerning this problem. Areal application problem has been presented to show the efficiency of the performance of our model and the method. Finally we obtained some results by randomly generating some problems.