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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
Mon Sep 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
الهــــــــــدم الخــــــــــــلاق Creative Destruction وإمكانية اعتماد كنموذج ابداعي في المنظمات العربية
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أن هذه الدراسة هي دراسة نظرية اهتمت بتقديم مدخل معاصر لمنظمات الأعمال، يمكن أن يعتمد علية من أجل تحقيق الريادة و البقاء. وذلك من خلال اعتماد مدخل الهدم الخلاق و تقديم أنموذج قادر على التفاعل مع البيئة بكل ما تقدمه من فرص وتحديات.

وتم تقسيم هذه الدراسة إلى ثلاثة مباحث،تناول المبحث الأول منهجية الدراسة. وبينما تناول المبحث الثاني توضيح مفهوم الهدم الخلاق والعناصر المكونة لهذا المدخل وأخيراً

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Publication Date
Wed Nov 28 2018
Journal Name
Arab Science Heritage Journal
اعتراضات اعتراضات الـخوارزمي الـنحوية في كتـابه التخمـير عـلى الـزمـخشـري ( قسم الأسماء )
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Abook of alzmkchri (AL-Mefsal) considers one of the most book familiarities among grammarians whom begin to explain it importance kitab AL-Takhmair for Khwarizmi separated opinions in grammatical schools that dealt with.

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Publication Date
Wed Nov 14 2018
Journal Name
Arab Science Heritage Journal
توظيف توظيف التراث في المونودراما المسرحية (نصوص د. علي حداد أنموذجاً)
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Arabic humanity heritage had considered as a treasure of artistic, literary aspects, which is full of energies to embody investment by suitable historical ideology.

Theatre, art can be used, corresponded to make special essay reflecting a desire to establish cultural notification.

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Publication Date
Sun Jul 01 2007
Journal Name
Political Sciences Journal
عرض رسائل (الموقف من التعددية الحزبية في الفكر السياسي الاسلامي المعاصر)
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عرض رسائل (الموقف من التعددية الحزبية في الفكر السياسي الاسلامي المعاصر)

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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
Tue Dec 31 2019
Journal Name
Arab Science Heritage Journal
حفظ حفظ القرآن الكريم ودوره في تعليم اللغة العربية للناطقين بغيرها
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When Allah has chosen Arabic language to be the eternal language of the Holly Qura'an, Qura'an was the original resource of the perfect grand Arabic

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
دور ومسؤولية مراقبي الحسابات في العراق تجاه الأفصاح الألكتروني للقوائم المالية
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This research aims at shedding light on the electronic disclosure of the financial information under the condition of the development of this kind of disclosure all over the world , and its effect  on the job of auditing and accounting . It also aims to show the extent to which the observers of accounts are aware of their duties towards this kind of disclosure and to test the effect of some environment factors on the level of this awareness.

To achieve the aims of the research has been divided in to four parts. The first one deals with mathadolge of the research. The second parts is devoted to the theoretical aspect of the research referring to the notion of electronical, disclosure its features and effect on the auditing jo

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Publication Date
Sun Jan 02 2005
Journal Name
Political Sciences Journal
عرض اطروحة (نهضة الامة العربية والاسلامية في فكر مالك بن نبي)
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نهضة الامة العربية والاسلامية في فكر مالك بن نبي

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Publication Date
Wed Nov 28 2018
Journal Name
Arab Science Heritage Journal
جوانب جوانب من المعالجات البيئية والمناخية لعمائر الطين في الواحات الليبية
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This paper sheds light on aspects of environmental and climatic treatments in the groves mud existing in some Libyan oases. It reveals the architecture efforts and contributions to the adaptation of the construction and materials in order to organize the weather inside the building blocks to suit the nature of the human and his living in all seasons

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Publication Date
Tue Jan 29 2019
Journal Name
Arab Science Heritage Journal
منهج النديم البغدادي في فهرسة دواوين الشعر (حتى نهاية العصر الأموي )
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الحديث عن محمد بن إسحاق النديم حديث عن عالم جليل كان له فضل تصنيف سفر خالد من أسفار المعرفة و العلم و سجل ضم عناوين ما أنتجته الأمة العربية الإسلامية في وقت عزها و مجدها و سطوع كوكبها في سماء الدنيا ، فجاء هذا الكتاب جامعا نافعا في بابه .

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