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Experimental Study on the Effect of Insertion of Copper Lessing Rings in Phase Change Material (PCM) on the Performance of Thermal Energy Storage Unit
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Abstract

One of the most suitable materials to be used in latent heat thermal energy storage system (LHTES) are Phase change materials, but a problem of slow melting and solidification processes made many researchers focusing on how to improve their thermal properties. This experimental work concerned with the enhancing of thermal conductivity of phase change material. The enhancing method was by the addition of copper Lessing rings in phase change material (paraffin wax). The effect of diameter for the used rings was studied by using two different diameters (0.5 cm and 1cm). Also, three volumetric percentages of rings addition (3%, 6% and 10%) were tested for each diameter. The discharging process was done with four velocities for each case. The obtained results indicated that the maximum volumetric percentage gave a diminished time for melting and maximized the heat transfer in both PCM and air sides as compare with the case of no rings, but the effect of these rings had lower effect on the solidification time. In case of 1 cm rings diameter minimum time for melting was obtained for both 3% and 6% volumetric percentages as compared with the same percentages in case of 0.5 cm diameter rings, while the latter with 10% volumetric percentage overcomes the 1 cm diameter rings for the same previous percentage. Also it can be seen that the minimum velocity (v=1m/s) gave the utmost outlet temperature and with the maximum one (v=3m/s), the minimum solidification time achieved.

Keyword: Thermal energy storage systems, Latent heat storage, Phase change materials, Heat transfer enhancement.

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Publication Date
Sun Feb 07 2021
Journal Name
مجلة العلوم الاقتصادية والإدارية
تقويم كفاءة القطاع البلدي في محافظة الانبار باستخدام النهج اللامعلمي (DEA)
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The research aims to measure, assess and evaluate the efficiency of the directorates of Anbar Municipalities by using the Data Envelopment Analysis method (DEA). This is because the municipality sector is consider an important sector and has a direct contact with the citizen’s life. Provides essential services to citizens. The researcher used a case study method, and the sources of information collection based on data were monthly reports, the research population is represented by the Directorate of Anbar Municipalities, and the research sample consists of 7 municipalities which are different in terms of category and size of different types. The most important conclusion reached by the research is that there is a variation in the efficien

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Publication Date
Wed Dec 01 1999
Journal Name
مجلة کلیة الکوت الجامعة للعلوم الانسانیة
ما تمحّل له ابن جني من القراءات الشاذة في كتابه المحتسب
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Publication Date
Sun Jul 03 2011
Journal Name
Journal Of Educational And Psychological Researches
المشكلات التي تعاني منها المرأة العراقية الأرملة في ظل الظروف الراهنة
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This research aims at identifying problems  that the  Iraqi widow woman suffers from. The research is limited to a Sample of terrorism victims widows which is up to (70) widows from Al-Amal center for widows and orphans care in Baghdad.                                                                                <

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Publication Date
Sun Dec 23 2018
Journal Name
Arab Science Heritage Journal
قراءة قراءة نقدية في موارد كتاب الضوء اللامع للسخاوي (ث 902هـ)
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The book (Al-Thaw’ Al-Lami’) (Bright Light) by AlSakhawi is one of the most important historical sources in the Hijri ninth century. In this book, the author mentioned the biographies of most famous scientists and other authors browsing the most prominent scientific

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Publication Date
Thu Nov 21 2024
Journal Name
مؤتمر
استراتيجية الأمن السيبراني ودورها في تحقيق أهداف التنمية المستدامة: العراق انموذجاً
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Publication Date
Sun Jul 01 2012
Journal Name
Journal Of Educational And Psychological Researches
الاشكال المفضلة لدى اطفال الرياض ونسبة توظيفها في تصاميم اثاث الرياض
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The research explores the shapes preferred by children and the extent to which it can be utilized on the experimental kindergarten at the Woman’s School of Education. To achieve the goal, the researcher has displayed pictures that have been chosen from within the research boundaries which represent four categories: Geometrical shapes which included (squares, rectangles, triangles, and circles), agricultural shapes which included (apples, oranges, bananas, and grapes), motion pictures shapes (cartoon characters) which included (Jerry the mouse, Twitty the bird, Bugs Bunny the rabbit, and Winnie the pooh), and animal shapes which included (dogs, fishes, frogs, and horses) to the sample children of (60) child (boys and girls) that

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Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
العامل العامل الاقتصادي وأثره في نشوء المدن الإسلامية وتطورها ( بخارى ) أنموذجاً
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After atour-For quite somtime,in the field of research and investingation on the economic aspects and the impact of her money is mportantin the evolution and emegece of the Islamic countres,especially including especially Morkhana him specimer nigh borhood the countries of the mashreq al islami,searhout,among other things summarilesas

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Publication Date
Mon Oct 22 2018
Journal Name
Arab Science Heritage Journal
السحر السحر وعقوبته في المجتمع الإسلامي من خلال القرآن والسنة النبويةالشريفة
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إن المعتقدات الخاصة بالسحر والعرافة قديمة جدا كون الإنسان عرف الكثير منها ومارس أنواع من الأساليب السحرية منذ أقدم العصور ومن أكثر العلوم التي حرم تعليمها ونشرها هو علم السحر والسيمياء أو الكيمياء والشعبذة والحيل . ومع ذلك عرف السحر من قبل سكان بلاد وادي الرافدين ولاسيما في بابل والسحر يمثل أقدم مرحلة في تطور العقل البشري .

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Publication Date
Sat Mar 02 2024
Journal Name
مجلة الذكوات البيض
أشكالية توظيف الخطاب السياسي ودوره في تعزيز السلم المجتمعي: العراق انموذجا
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لكل دولة في هذا العالم خطابها السياسي والذي يحدد سياستها الداخلية والخارجية، وهي سياسة ثابتة تنطلق من مفاهيم وبرامج وثوابت تخدم مصالحها الحيوية، لكون الخطاب السياسي ليس مجرد كلام عابر في عالم السياسة الدولية وانما هو ثوابت مهمة يحدد توجهات هذه الدولة او تلك ويحدد دورها الدولي وطبيعة العلاقة مع البلدان الاخرى ومنها الدول المجاورة لها. شهد العراق بعد العام 2003 تحديات جديدة تمثلت بتغليب خطابات الطائفية والكراه

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Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
استخدام استخدام نظم المعلومات الجغرافية في الدراسات الاثارية ( تنقيبات جامعة الموصل).
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GIS is characterized by great potentialeties to deal with huge geographical data and conclude what is necessary for it. It was very useful to get use of the potentialities of this system of GIS in the field of archaeology and to harvest very accurate results in a relatively short time, compared to the old archaeological methods.

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