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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
Fri Jan 04 2019
Journal Name
Journal Of Planner And Development
نمذجة توزيع المدارس الابتدائية في مدينة الفلوجة باستخدام نظم المعلومات الجغرافية G.I.S
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Publication Date
Mon Oct 15 2018
Journal Name
Arab Science Heritage Journal
نحو نظام نحو نظام لغوي عربي متوازن في المساواة بين الرجل والمرأة
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We must live in an era dominated by the call for equality between men and women, in which the voices of advocates of gender integration were heard. After women opened their doors to compete with their brother, Knowledge, and culture in the various forms of life, language as a science of the time and knowledge of the other had to match this reality and express the most accurate expression of this task

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Publication Date
Tue Jun 03 2003
Journal Name
Al-academy
التسليات في البلدان الاسلامية مشاهد حياة الطرب والالات الموسيقية كما يعكسها الفن
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التسليات في البلدان الاسلامية مشاهد حياة الطرب والالات الموسيقية كما يعكسها الفن

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Publication Date
Tue Dec 31 2013
Journal Name
Journal Of The College Of Languages
إيقــاع النفـــس الشـــاعـرة في شعر الشاعر الصّقلي علي بن عبد الرحمن البلـَّنوبي
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درست الباحثة البنية الإيقاعية عند الشاعر الصقلي

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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
Fri Jan 04 2019
Journal Name
Journal Of Planner And Development
تقييم الأحوال الاقتصادية للمعيشة في مدينة الموصل: السكان والمساكن للمدة 2004-2007
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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Educational And Psychological Researches
مدى معرفة واستعمال تدريسيو اقسام الجغرافية في كليات التربية لتطبيقات التعليم الالكترونية
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Abstract The present research aims to know the range of Knowledge and the using of teachers of aerography department in colleges of Education to Applicant electronic Learning , So the Sample of the research reached (129) teacher, of the university of Boghdad and Al mustansiria who were chosen by using Randomly sample , and applauding questioner for these perpos that prepared by muhamed bn Ghazi Al Judi – and by using the T-test for one sample and person correlation formula as a statistical means. The research reached to the results which indicate that weakness knowledge and using the theachers of geographe department to the application electronic learning. And according this the researcher put some Recommendation and suggestions. 

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Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
وجوه من وجوه الاعجاز البلاغي في القرآن الكريم الايجاز (جوامع الكلم أنموذجاً)
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        The subject of the research is the collective words = Jawami Al-kalim. Those who wants to know this subject to be aware of the benefit of  "Al-Ejaz and Al-iktisar " and to cover the Rhetoric of signal should think carefully the abbreviations because the collective words because it is the a face of the important faces represented by the abbreviation of shortness as it is and old subject where it can be found in every source of rhetoric books which were old or modern. But what attracts attention is that this subject did not take all its range in study in the way that discover its beauty concerning style, words, sentences and meaning. This cause

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Publication Date
Sun Oct 14 2018
Journal Name
Arab Science Heritage Journal
الاجراءات الإجراءات الإدارية والقانونية وسبل معالجتها لآزمة الأراضي في بغداد 1932-1938
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شكلت السيطرة العثمانية على العراق  حقبة تاريخية مهمة ، حيث وضعت فيها ركائز عدد كبير من الأنظمة الأدارية  فغدت  الأساس للتنظيمات  فيما بعد ومنها  الإجراءات الإدارية والقانونية وسبل معالجتها لآزمة الأراضي في بغداد1938-1932.

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Publication Date
Wed Jun 01 2016
Journal Name
Journal Of The College Of Languages (jcl)
כאבי הילדות ברומן האוטוביוגרפי (סיפור על אהבה וחושך )של עמוס עוז
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תקציר

הילדות נחשבה השלב חשוב בתולדות האדם, וגם המשפיע ביותר בהיווצרות של אישיותו, משום שבו תתהווה את הליבה של ציוני דרך אישיותו של האדם, ויתגבש בו את ציוני דרכו ותכונותו שלו, וגם תשרטט את הבסיס העיקרי של מה יהיה האדם בעתיד. היות והילדות נשארה היא והשלכותיה בקרבו של האדם, עם זכרונותיה היפות והעצובים כאחד, במחקר זה עסקנו בילדותו של הסופר עמוס עוז כסיסמה לפענוח לדמותו, ולספרותו, כמו כן לכאבים שהעברו

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