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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 Jan 01 2023
Journal Name
مجلة المستنصرية لعلوم الرياضة
الثقافة التنظيمية لدى اللجنة الأولمبية الوطنية العراقية من وجهة نظر أعضاء الهيئات الإدارية في الاتحادات الرياضية
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Publication Date
Mon Jul 22 2019
Journal Name
Arab Science Heritage Journal
الاسطوغرفيا العثمانية التركية حول ثيمة محمية الجزائر في الفترة العثمانية ما بين - الموضوعية العلمية والذاتية المؤدلجة
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تضمّنت الاسطوغرافيا العثمانية التركية حول ثيمة محمية الج ا زئر في -
الفترة العثمانية مؤلفات صُبغت بعضيا بطابع الموالاة والتحيّز

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Publication Date
Tue Aug 31 2021
Journal Name
معرفة
نسبة مساهمة التدفق النفسي في بعض مهارات الجمناستك الإيقاعي و فعالية رمي الثقل بالساحة و الميدان
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Publication Date
Sun Jan 13 2019
Journal Name
Arab Science Heritage Journal
دراســـة الموارد في كتاب البدر الطالع بمحاسن من بعد القرن السابع للشوكاني(ت 1250 هـ - 1834م )
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تُعد دراسة أعلام الفكر العربي والإسلامي من أهم الدراسات التاريخية ولا يمكن للأمم المتحضرة أن تنسى علمائها ومفكريها لما لهم من دور كبير في حاضر الأمة ومستقبلها و تاريخنا الإسلامي يحفل بالعديد من العلماء ورجال المعرفة  الذين ساعدوا على تقدم ورقي العرب والمسلمين على الأمم الأخرى0

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Publication Date
Sun Dec 02 2018
Journal Name
Arab Science Heritage Journal
عبدالحميد الثاني والإستيطان الصهيوني في الولايات العربية من مشرق الوطن العربي مناطق الأختيار للإستيطان فلسطين والعراق
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ترك السلطان عبدالحميد الثاني بصماتهُ على أخاديد الزمان وعلى خارطة المشرق العربي الخاضع للسيطرة العثمانية أنذاك ، لكونهُ أهم شخصية أسلامية غير عربية واجهت الخطر الصهيوني ومحاولاتهم الإستيطانية في مشرق الوطن العربي ، على الرغم من صعوبة الظروف التي كانت تمر بها الدولة العثمانية داخليا ً وخارجيا ً، بما فيها من أطماع اقتسامها بين الاوربين ولذا سموها بالرجل المريض .

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Publication Date
Mon Jul 22 2019
Journal Name
Arab Science Heritage Journal
سرور سرور الفؤاد بالصافنات الجياد في معرفة الخيل وأسمائيا لمشيخ محمد العمري )د ا رسة وتحقيق(
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تضمن البحث تحقيق مخطوط"، سرور الفؤاد بالصافنات الجياد في معرفة الخيل
وأسمائياالشيخ محمد العمري" وكما ظاىر من عنوان المخطوط إنوُ يتناول الخيل، والخيل
موضوع ميم في حياة العربي قبل الاسلام باعتباره يمثل جزءاً من تفاصيل حياتو الملازمة لوُ
واعتماده عمييا ىذا أولاً وثانياً ماتحمموُ الخيول من معاني الفروسية والعنفوان وماتثيره في
الأنسان من حب الأقتناع والمتعة المتحققة من النظر إلييا وحبو لمسبق،

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Publication Date
Mon Sep 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Synthesized 2nd Generation Zeolite as an Acid-Catalyst for Esterification Reaction
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MCM-48 zeolites have unique properties from the surfaces and structure point of view as it’s shown in the results ,and unique and very sensitive to be prepared, have been experimentally prepared and utilized as a second-generation/ acid - catalyst for esterification reactions of oleic acid as a model oil for a free fatty acid source with Ethanol. The characterization of the catalyst used in the reaction has been identified by various methods indicating the prepared MCM-48 is highly matching the profile of common commercial MCM-48 zeolite. The XRF results show domination of SiO2 on the chemical structure with 99.1% and  agreeable with the expected from MCM-48 for it's of silica-based, and the SEM results show the cubic c

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Publication Date
Mon Mar 23 2020
Journal Name
Journal Of Engineering
Improving Photovoltaic Panel (PV) Efficiency via Two Axis Sun Tracking System
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In this paper two axis sun tracking method is used to absorb maximum power from the sun's rays on the solar panel via calculating the sun’s altitude and azimuth angles, which describe the solar position on the Iraqi capital Baghdad for the hours 6:00, 7:00, 8:00, 9:00, 12:00, 15:00 and 17:00 per day. The angles were calculated in an average approach within one month, so certain values were determined for each month. The daily energy achieved was calculated for the solar tracking method compared with the fixed tracking method. Designed, modeled and simulated a control circuit consisting of reference position truth table, PI Controller and two servomotors that tracked the sun position to adjust the PV panel perpendicular

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Publication Date
Mon Dec 11 2017
Journal Name
Al-khwarizmi Engineering Journal
Iraqi Bauxite and Porcalinite Rocks Based Refractory, Preparation and Studying Properties
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Abstract 

Locally natural occurring Iraqi rocks of Bauxite and Porcelanite (after pre calcinations at 1000oC for 1hr) were used, with the addition of different proportions of MgO and Al2O3, to prepare refractory materials. The effects of these additives on the physical and thermal properties of the prepared refractories were investigated.

Many batches of Bauxite/MgO, Bauxite/Al2O3, Bauxite/MgO/Al2O3, and   Porcelanite/ MgO/Al2O3 were prepared. The mixture is milled and classified into different size fractions; fine (less than 45μm) 40%, middle (45-75μm) 40%, and coarse (75-106μm) 20% .

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Publication Date
Sat Mar 30 2013
Journal Name
College Of Islamic Sciences
 المسائل المتعلقة بالأسماء الثابتة لله (عزوجل) الواردة في (مرعاة المفاتيح شرح مشكاة المصابيح، لأبي الحسن المباركفوري (ت1414هـ).
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The research deals with the issues related to the fixed names of God U, which are from a set of issues mentioned in the Book of Observations of the Keys Explaining the Mishkat al-Masbah by Abu Al-Hasan Al-Mubarakfory (d. 141 AH). It included five demands: the first of them is in proving and identifying the most beautiful names and divisions of God, and the second in the name, name and name. And the third: It was in their number, while the fourth: in deriving the names, is it suspensive or not? And Fifth: The Compilation of Allah’s Most Beautiful Names.

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