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 individual average income is considered one of the most used criteria for the distinguishing between the developed and the developing countries, for this reason the efforts of economic development has been construed on increasing the average national income, the investment expenditures is considered one of the basic foundations for economic development operation which lead to the expanding the prodection power of the economy, and increasing the level of national income in an averages greaten than the primary expenditures due to the work and interaction between the multiplier and the accelerator. But the ability of the economic sectors in the generation of national income as a result of the primary expenditures is different fr
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The research study aims to investigate the prevalence of the phenomenon of drags and the causes of this phenomenon from the teachers point of view Two hundred Teachers participated in this study Questionnaire was used to collect the data .
The results emphasized the importance 0f the educational counseling through different procedure to prevent drugs abuse . the results also&
... Show MoreGod Almighty singled out Arab nation to carry divine messages، and make them the land of Iraq to store the soil prophets and apostles and grandchildren of Al al-Bayt، peace be upon them as they were and are still a beacon for people، Shrines and monuments and flags، frequented by science students from various walks of life، were are shrines representing the name of Iraq by the private and the nation of Islam in general، sung by the preacher and artist and writer
This research investigates the methods of producing Investigative Arabic Television Programs that are able to prove its existence during a short period of time as a form of Television programs on Arab satellite channels growing in number and varied in content. The research aims to present qualitative and quantitative descriptions of the methods used in tackling the topics discussed in the program, and knowing whether they satisfy the conditions and scientific foundations for the research, investigation, analysis, and interpretation. The researcher uses the survey method and uses the tool of content analysis including a set of methodological steps that seek to discover the implied meaning of the research sample represented by the program
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This study aims at assessing the availability of national values in the curriculum of the first three grades in Jordan. The study also aims at the nature of distributing these national values. The sample of the study consists of the curriculum of math, science, Arabic language, Islamic education, and national and civil education in Jordan. To achieve the aims of the study, the researchers used the analyzing approach, and they also depended on the referential statement for the general and minor objectives as a tool to analyze and numerate. The results of the study shows that the concentrating on the n
... Show Moreهدف البحث الى الكشف عن فاعلية استراتيجية المماثلة في تحصيل مادة الكيمياء والذكاء الانفعالي لطلاب الصف الخامس العلمي الاحيائي. وتكونت عينة البحث من (28 ) طالبا من طلبة الصف الخامس العلمي الاحيائي في اعدادية الشاكرين للبنين, التابعة لمديرية تربية بغداد – الكرخ الثانية, موزعين بين شعبتين بالتساوي, شعبة (أ) وهي المجموعة الضابطة التي درست على وفق الطريقة الاعتيادية, وشعبة ( ب) وهي المجموعة التجريبية والتي درست على و
... Show Moreتحيا الأمم بتراثها فهو الأساس الذي تنطلق منهُ، وما من أمة إلاّ ولها تراث، وهو سر حياتها وديمومتها ، فالأمة العربية الأسلامية لها تراث تليد التي تشرفت بحمل أقدس رسالة سماوية وأكملها لأمم الأرض، فكانت نبراساً أهتدت به البشرية حتى انتشلتها من واقعها المريض إلى أرغد عيش وأقوم خلق وأنبل نفس .
يهدف البحث الحالي إلى معرفة اثر التدريس بطريقة التنقيب الحواري في حفظ النصوص الأدبية لدى طلبة قسم اللغة الكردية، اختارت الباحثة طلبة المرحلة الثانية في قسم اللغة الكردية بكلية التربية ابن رشد، للعام الدراسي
(2008-2009) ميدان لتطبيق تجربتها.
تألفت عينة الدراسة من (48) طالبا وطالبة، تم توزيعها عشوائيا إلى مجموعتين، مجموعة ضابطة (درست بالطريقة الاعتيادية) تألفت من (23) طالبا وطالبة ومجموعة تجريبية (درست بطريقة الت
This paper represents an experimental study on the application of smart control represented by the use of the fuzzy logic controller. Two-link flexible manipulators that are used in airspace and military applications are made of flexible materials characterized by low frequency and damping ratio. To solve this problem, this paper proposes the use of smart materials (piezoelectric transducers), where each link is bonded with a pair of piezoelectric transducers that act as a sensor and another as an actuator. As the arm vibrates because of the movement generated by the motor, this voltage is controlled by a regulator inside the LABVIEW® 2020 software and sends the output control voltage to the piezoelectric actuator. Experimental results
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