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.
Abstract
The research aimed to prepare an audit program focusing on the activities of municipal institutions related to the environmental dimension as one of the dimensions of sustainable development, and applying the program for the purpose of preparing an oversight report related to assessing the impact of the activities of municipal institutions on the environmental reality as the main channel through which municipal institutions contribute to achieving the part related to it. Among the requirements of sustainable development, the proposed program was prepared and applied to the institutions affiliated to the Directorate of Mu
... Show Moreالسياسة الروسية في الشرق الاوسط الكبير او (فن اقامة علاقات الصداقة مع كل دول العالم)
Performance measures are a central component of management control system, making good planning and control decisions requires information about how different subunits of organizations have performed. To be effective, performance measures (both financial and nonfinancial) must also motivate managers and employees at all levels of organization to strive to achieve organization goals.
To give aclear picture about performance must be used compound measure, that was best than single measure.
Altman model can be used as a compound performance measure that measures the performance by tied a sum of variables, due to make weight for every variable to reach for performance.
The study aimed at identifying the level of administrative work quality of private Schools principals at Southern Governorates of Palestine from the teachers' point of view in their schools. To achieve the objectives of this research, a questionnaire was prepared by the researcher consisted of (28) items. It was applied to a sample of (350) teachers. The researcher adopted the descriptive-analytical approach. The results of the study showed that the degree to which principals of private schools in the southern governorates of Palestine practice Administrative Work Quality from the viewpoint of their teachers was very high, with relative weight (85.00%). The results also showed that there are statistically significant differences at the l
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The aim of this study is to find out the effect of reciprocal teaching on the fifth literary class pupils in acquiring the skill of geographic map reading. The researcher uses the partial experimental design/pre- post-test for two equivalent control and experimental groups.
The population of the study is represented by the fifth literary class pupils at a school of the Directorate of Education /Baghdad Karkh second. The sample is selected randomly as section (A) the experimental group and section (C) the control group. The sample total number is (60) pupils, (30) pupils for each group. The two groups are equalized in the following variables: IQ, age and the pupils’ previous geog
... Show MoreIrak Türk ağızları Azeri Türkçesinin bir uzantısı olarak değerlendirilir.Kerkük Türkçesiyle yazılan edebi ürünler, Irak Türkçesinin tamamını ifade etmek üzere kullanılmaktadır. Zamanın Eli divanı Kerkük Türkçesile yazılan bir eserdir. Bu yüzden bu divanı seçtik ve Irak Türkmen Türkçesi , Osmanlı Türkçesi ve Türkiye Türkçesi dilleri arasında karşılaştırmalı bir inceleme yaptık.
Bu araştırma, Irak Türkmen şairlerinden birisi sayılan Es’at Naib’in şiirleri üzerinde uygulamalı bir çalışmadanoluşmaktadır. Bu çalışmada adı geçen şairin “Zamanın Eli” Divanından bazışiirlerini önce yeni Türkçeye çevirdik vedaha sonra isim ç
... Show MoreResearch aims at evaluating the quality of the teaching skills of math teachers in junior high / scientific branch from their point of view.
The researchers prepared for this purpose a quality of teaching skills standards questionnaire, It consisted of 72 items distributed on four axis, The research sample was 200 teachers The researchers used statistical methods: the arithmetic mean, standard deviation, variance test, test Shiva , The results showed a statistically significance difference Attributed to the qualification variable in the second axis (Planning for teaching topics) And the absence of statistical difference function,
... Show Moreتعد البرمجة الخطية عاملاً مؤثراً وفعالاً في عملية صنع و إتخاذ القرار عندما تكون الموارد متاحة أو متوفرة لكي تعطي أهدافاً معينة ، وتكمن البرمجة الخطية في حل وتقييم الانشطة أو الفعاليات عند تطبيق إحدى أدواتها وهي الطريقة المبسطة العامة ، التي يكون فيها الحل مقبولاً (ممكناً) ويجب التوصل الى الحل الامثل عندها تسمى بالطريقة المبسطة الاولية أو يكون الحل فيها أمثلاً ويجب التوصل الى الحل الم
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Peaceful coexistence is not seen as a new topic of secretions of modern civilization, a requirement to solve the problems of our era or one of the indications of urgent immediate needs, rather, tolerance is considered basis for building a state. Therefore, we can touch on the principles and basics of tolerance in the Holy Qur’an, the speeches of the Messenger (may God bless him and grant him peace) and his hadiths, and the principle of brotherhood that he established