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 teacher is the most able to achieve the goals of education in education because he has the ability to affect the behavior of the disciples testified and its actions and appearance and other actions that convey pupils with it sometimes in a manner unconscious or unconscious , and the importance of the role of the teacher in the educational process , it is necessary to compromise the care and attention to the extent that commensurate with the important role that the rise in the preparation of youth and composition , and as a result is needed to continue efforts to improve the quality of teacher preparation so that it can be more effective and positive in the educational process .
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In this paper we define and study new concepts of fibrewise topological spaces over B namely, fibrewise near topological spaces over B. Also, we introduce the concepts of fibrewise near closed and near open topological spaces over B; Furthermore we state and prove several Propositions concerning with these concepts.
يهدف البحث لمحاولة دراسة واقع ادارة الوقت لدى عينه من رؤوساء الأقسام العلمية في كليات ومعاهد هيئة التعليم التقني اذ بلغ حجم العينة (47% ) فرداً تم احتيارهم عشوائياً من (15) كلية ومعهد موزعة في (69 من محافظات القطر وبلغ حجم عينة البحث (17%) من عدد رؤوساء الاقسام العلمية في الهيئة ، ولغرض جمع البيانات تم أعداد استمارة استبيان تمت صياغتها بشكل يؤمن توثيق الوقت الفعل
... Show Moreاتجهت دول العالم الى تسخير جميع الإمكانيات والخبرات والعلوم من اجل الوصول الى مستويات متقدمة في الرياضات المختلفة ويهدف التدريب الرياضي إلى إعداد اللاعبين إعدادا جيدا تكمن مشكلة البحث من خلال خبرة الباحثتان الميدانية ومتابعة تدريبات لاعبي المدرسة التخصصية كرة اليد فقد لوحظ هناك ضعف واضح في الأداء المهاري ولابد من تطوير أوجه الضعف لتحقيق مستوى انجاز افضل . ويهدف البحث اعداد تمرينات خاصة بأستخدام جهاز ا
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Parmi les oeuvres d'Albert Camus, qui s'éloignent un peu de sa
tendance générale qui traite les thèmes de l'absurde ,du néant et de la
question de la mort , on trouve son recueil "l'Exil et le Royaume" 1957
qui contient six nouvelles qui sont d'une invention moins épouvantable
(le Renégat , la Femme adultère , les Muets , le Pierre qui pousse , l'Hôte
et Jonas). Ces nouvelles , à l'exception du "Renégat" , ne provoquent pas
les questions philosophiques et dialectiques qui dominent la plupart des
oeuvres d'Albert Camus , Mais ces nouvelles traitent tout simplement la
question d'homme exilé dans son existence et sa recherche perpétuelle
de son royaume.
The research aim to know the effect of note–taking by computer method as amentalactivators in achievement of physics subject for the first intermediate class students.
To investigate from aim of the research the research sample was chosen from the first intermediate class students in Al–mutamyzat secondary school for girls. Which belongs to the general administration for the second karkh education which randomly chosen from (9) schools for distinct female students in Baghdad. Then randomly chosen two sections form three about (80) female students at (66.667%) from total sample it’s about (120) female student in the three sections. The randomly chosen too, section (a) to represent experimental group it’s about (41) female
... Show MoreOne of them one of the important books due to its containing valuable information written by the author. Information include the life of the Messenger (Peace be upon him)
this research aims it measure the technical efficiency of the branches of the General Company for Land Transport, That scattered geographically at country level, by Data Envelopment analysis (DEA) technique, as this technique relies on measuring the efficiency of a set of asymmetric Decision making units, which is one of the nonparametric mathematical methods for and application related to Linear Programming, and this is what helps the General Company for Land Transport to diagnose its branches performance by benchmarking with each other and determine the performance gap. The research found that there is variation in the level of efficiency in the company's branches