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 intellectual and revolutionary movements that have emerged since the beginning of the second half of the first century of the Islamic era did not appear suddenly, but must have preceded by a social consciousness, multi-forms, in the forefront of class awareness and religious awareness, and awareness was more painful, Of the society of the Arabian Peninsula - before Islam - feel it and suffer from it, a sense of injustice and tyranny, oppression and humiliation, and the destruction of dignity as well as poverty and hunger, and the injustice of tribal laws, and tyranny of each other and the tyranny of their heads on the tribes members and families belonging to this tribe or hill
The role of the Abbasid Caliphate in strengthening the business with the Indian subcontinent and development. Came upon Baghdad and the shift of succession to Iraq in the forefront of efforts made by the Abbasids to revive the trade with Eastern countries, given that the commercial was targeted among other factors,'s location in Iraq amid the ancient world among the countries of Turk
تمت دراسة سرعة الاخلاف في النوع Branchiura sowerbyi وعلاقتها بدرجات الحرارة حيث لوحظ ان قابلية هذه الديدان على اخلاف الحلقات الجسمية التي تحوي على الخيوط الغلصمية تكون اسرع من قابليتها على اخلاف الحلقات الجسمية الاخرى وبنسبة موت اقل خاصة في درجة حرارة ( 20 ± 3 ) م°.
الامن الجماعي في اسيا .. بقلم : لونيك فرو وار
Islam has paid great deal of attention to land issue where has been
considered most resources for providing Muslims with water and food and
building on that we notice that the Islamic government worked hardly to give
attention ton the land especially newly included under control of Muslims
especially that they had got with out fighting or bloodshed but had been
included via reconciliation with the landlords so the Muslims had share in that
would be taken either in cash or in materials in a value would be differentiated
following several issues like type of harvest and method of watering the land
and religion of the landlords.
So Muslims had listed laws and rules that enable them typical investment
for that l
همجوارى جغ ا رفياى ميان عربها واي ا رنيان نقش بز رگ در بروز آشكار برخى از روابط وعلاقه
هااى مياان دو زباان عرباى وفار اى وهمچناين مياان دو ادبيااا عرباى وفار اى وگويناد كاه ادبيااا
فار ى قديم اولين ادبياا خارجى كاه باه ادبيااا عرباى مبوا، باود وهماين باعا انبشاار زباان عرباى
در اي ا رن شد. وبعد از فبح ا لامى زبان فار ى بيشبر وا ه ژ هاى خود از زبان عربى گرفاا همچناين
به زبان عربى ب يارى از وا ه ژ هاى وادر كرد
يناقش هذه البحث فكرة الهوية الوطنية العراقية عند الإمام محمد تقي الشيرازي، والوقوف على دراسة سيرته الذاتية والعلمية، وتحديد مواقفه السياسية، ورؤيته لفكرة الهوية الوطنية العراقية، من خلال البحث والتحليل لأبرز مواقفه ورسائله وافكاره السياسية.
مكانية استخدام السوق المالية في التنبؤ بالدورات الاقتصادية
المقدمة
تجدد الاهتمام بموضوع نوعية حياة العمل (Quality of life) الذي يرمز له اختصارا (QWL)، في السنوات الأخيرة الماضية، وبمطلع الألفية الثالثة على وجه التحديد، من قبل الباحثين الأكاديميين والمهتمين الممارسين في منظمات الأعمال، وذلك بوصفهم إليه بأنه أهم مصادر الرضا للعاملين، والعنصر المميز لبيئة عمل منظمة ما عن غيرها. وهنا، قد برزت الاضطلاع بالمسؤولية الأخ
... Show Moreانطلاقاً من ضرورات التجديد والتطوير لمجلتنا العزيزة، ستجرى اضافات عليها بين الحين والآخر، قد تتناول شكلياتها و/ او محتوياتها. والبداية ستكون بترجمة المقالات والبحوث التي تقع في اختصاصها من المجلات الاجنبية المرموقة عالمياً، فإختارت هيئة التحرير المقالات الخمسة التي سيرد ذكرها لاحقاً للقيام بترجمتها بأسلوب علمي يعطي للتصرف والاضافات حدوداً لتصبح مقبولة وسهلة على القراء. فالمهمة هذه وان كانت صعبة وتت
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