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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 Sep 05 2021
Journal Name
جامعة بغداد/ كلية التربية للعلوم الصرفة - ابن الهيثم
امتلاك الطالبات لمهارات التفكير المنظومي المتضمنة في كتاب الرياضيات للصف الثالث المتوسط
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Publication Date
Mon Dec 26 2022
Journal Name
Arab Science Heritage Journal
العمق الوجداني والانفعال العاطفي لدى شعراء القرنين السابع والثامن الهجريين في الأندلس
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The Andalusi did not leave any poetic art without expressing his psychological and sentimental emotions and the depth of emotions and it sincerity. We found Andalusian translated his emotions into poetry and in many different subjects

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Publication Date
Sun Jun 07 2020
Journal Name
دراسات دولية
دور السياسة الخارجية العراقية في تفعيل الاداء الدبلوماسي لمرحلة مابعد العام 2003
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ان مرتكزات السياسة الخارجية العراقية لمرحلة ما بعد العام 2003 قد عكست توجهات ايجابية قادت الى صياغة مجموعة من الرؤى والتصورات الاستراتيجية الجديدة التي افضت الى اعتماد وتوظيف الوسائل والقنوات الدبلوماسية بوصفها وسائل فعالة وبطريقة متكاملة ومتوازنة من اجل تعزيز مستويات الاداء الفعلي وتحقيق جميع الاهداف المستقبلية للسياسة الخارجية العراقية في ضوء صياغة معادلة مفادها: تدعيم وترصين اداء مؤسسات صنع السياسة ال

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Publication Date
Fri Aug 15 2008
Journal Name
اطروحة دكتوراه
الاقليمية الدولية الجديدة في عالم ما بعد الحرب الباردة : انموذج آسيا الباسفيك
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The thesis discusses the concept of the new international regionalism that emerged after the growing effects and repercussions of globalization with its economic, political and security dimensions after the end of the Cold War and the crystallization of a different international system dominated by the United States of America, so that the major countries and actors in the international system realize the danger of globalization and move towards adopting regional arrangements to contain the negative effects of globalization. The Asia-Pacific model was chosen as a model for the study.

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Publication Date
Thu Apr 01 2021
Journal Name
Journal Of Engineering
Innovation Diffusion Elaboration into Architectural Movement
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The research investigates the term innovation and its role in elaborating architectural practice based on diffusion. The complexity of the architectural field compared with other fields shows a problem in explaining how innovations in architecture diffuse as a thought and act in a certain context of practice. Therefore, the research aims to build an intellectual model that explains the way personal thoughts resembled by unique models introduced by creative and innovator designers diffuse in a certain pattern elaborate these models into a state of prevailing thought resembled by the movement in architecture. The research will apply its model to the more comprehensive movement in architecture, which is the modern movement,

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Crossref
Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Educational And Psychological Researches
أثر برنامج التعبئة النفسية في مواجهة أحداث الحياة الضاغطة لدى طلاب المرحلة الاعدادية
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The Stressful Life Events consider one of the important thing in humans life in different period of life even school period,   where it is deal with vital period of life which is the youth period that represent the hope and precious resources that nation depend on it in building her civilization, structure anddevelopment  ,they are part from the present and whole future .As the great effect of stressful life event on humans , increase the need to put a program about psyching-up which consider one of the modren and effective programs.The aim of current search:1.   Measure the level of stressful events at the junior high school  studen

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Publication Date
Sun Oct 14 2018
Journal Name
Arab Science Heritage Journal
السل االدكتور محمد حسن سلمان الحمامي ودورهُ في مكافحة مرض التدرن الرئوي (السل
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Mohammed Hassan Salman is one of the Iraqi national figures who put a clear mark to promote the health institution and to improve the Iraqi people, even it was written about him as "The man who struggled to fight the tuberculosis", He began to struggle against this social courage that has been killing hundreds of Iraqis since his joining of Association for combating tuberculosis in 1999 and his big role in the application of (B-C-G) for the first in Iraq.

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Publication Date
Thu Dec 13 2018
Journal Name
Arab Science Heritage Journal
وسائل وسائل الاتصالات السريعة في حروب العرب المسلمين حتى منتصف القرن الرابع الهجري
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          This Study is concerned with The Fast communications in the wars of arab moslims until the middle of fourth century . it pointed to many communications for that , Like using the fast horses , and carrier pigeon , Almanader (Almanawin) wich used to tell for long distances , and drums , trumpets…

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
الأسطول والقوة البحریة في سلطنة عُمان خلال النصف الأول من القرن التاسع عشر
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Development and progress of the fleet and the navy in Oman during
the reign of Sultan Said bin sultan from 1804 to 1856.
It had second level in Arab Gulf and Indian Ocean during the first half
of nineteenth century. The fleet of Oman in this time became after British
fleet.
Several reasons were behind the development of Omani fleet
- First : The aim of Sultan Said was to built a large navy yard in Arab Gulf
and Indian Ocean to encourage him -to made many ships factories.
- Second: Arab Gulf and Indian Ocean within the reign of Sultan Said
wittinsed the confilicts and wars between different forces it drived Sultan Said
to built agood and strong navy.
- Third The main aim of Oman during the reign of Sultan

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Publication Date
Mon Sep 26 2022
Journal Name
جامعة بغداد/ كلية التربية للعلوم الصرفة - ابن الهيثم
مهارات التفكير المعرفي وعلاقته باليقظة العقلية لدى طلبة أقسام الرياضيات في كليات التربية
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