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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 Jan 07 2013
Journal Name
Journal Of Educational And Psychological Researches
انحراف الشخصية بحث ميداني في قضاء المدائن لمدينة بغداد
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This search modest deviation personal than to doubt that the event was not guilty by nature or offenders of evil in origin but is arictim of misfortune that makes him grow or live in the center of the corruption, even if he could be in the middle of the blessing of good and virtue and reform lived living righteousness and honor it was  a useful member for himself and his community and must state and family community take hands mnhrfaite in order to prevent and provide then

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Publication Date
Mon Jan 01 2018
Journal Name
حوليات كلية الآداب
الومضة في نصوص الريح لاتصادق أحدًا للشاعر لطيف هملت
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Publication Date
Sun Oct 01 2023
Journal Name
مجلة دراسات دولية
الذكاء الاصطناعي والوجود الإنساني: قراءة فكرية في الابعاد الاجتماعية
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Publication Date
Sun Apr 06 2014
Journal Name
Journal Of Educational And Psychological Researches
الكفاية في التعامل مع الضغوط لدى المراهقون العراقيين والجزائريين
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 This study tested the impact of region and gender on adolescents 'stress perceptions and coping styles. A total sample of 650 adolescents (5 9.4% female) from 2 countries (Iraq - Algeria). Samples of n = 325 were drawn from each country completed questionnaires on stress and coping behaviors in four domains (school, parents, peer, and future). Results revealed that levels of perceived stressfulness of issues in different domains were universally similar among adolescents from the two countries. School-related stress received the highest rankings, Parent- , future-, peer-related stress, ranked (second, third, and fourth) respectively. Differences emerged with respect to coping style depending on region and gender. Coping sty

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Publication Date
Sun Jun 30 2019
Journal Name
Journal Of The College Of Education For Women
القيادة الابتكارية لدى مديري المدارس الثانوية في محافظة بغداد
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 تكمن مشكلة البحث بان المؤسسات عامةـ والتعليمية منها خاصةفي الوقت الحاضرتواجه ظروف بيئيةتفرض عليها حتمية التغيير ، وذلك بسبب التحولاتالتي تحدثفي عالمناالحالي سواءًكان على المستوىالمحلي أو العالمي أو على المستوىالمؤسسة نفسها مما يجعلمؤسساتنا التربويةبحاجةملحةلمواجهة هذا التغيير القادم وذلك من خلال معالجةالمشكلاتالتي قد تظهر بطرق مبتكرة وابداعية مغايرةللطرقالتقليدية ،وذلك من خلال تهيئة المناخ الت

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Publication Date
Mon Oct 19 2026
Journal Name
Tikrit Journal Of Administration And Economics Sciences
دور تكلفة الانتاج الانظف في تحقيق الميزة التنافسية المستدامة
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يهدف البحث إلىبيان دور الانتاج الانظف وتأثير تطبيقه على تكاليف الوحدة الاقتصادية وادواته وتقنياته التي تساهم في دعم الميزة التنافسية المستدامة

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Publication Date
Tue Sep 27 2022
Journal Name
Arab Science Heritage Journal
اهمية المنهج القرآني في تخطيط المعالم العلمية للشخصية الاسلامية
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Human wealth is the most valuable wealth on the face of the earth, and building the intellectual, cultural and scientific human being is the greatest process carried out by all religions and philosophies at all times, and the divine law aimed at reforming the earth, including in order to preserve this great wealth, and to preserve its existential and qualitative entity.

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Publication Date
Mon Dec 26 2022
Journal Name
Arab Science Heritage Journal
الترادف في التعليق المغني لشمس الحق محمد العظيم آبادي
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Praise be to God, Lord of the Worlds, and prayers and peace be upon our master and beloved Muhammad and all his family and companions. As for what follows: The research presented the synonymous and common verbal expressions mentioned in the book Al-Taliq Al-Mughni on Sunan Al-Daraqutni by the scholar Sheikh Shams Al-Haq Muhammad Al-Azeem Abadi

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Publication Date
Sun Sep 19 2021
Journal Name
Journal Of Al-rafidain University College For Sciences ( Print Issn: 1681-6870 ,online Issn: 2790-2293 )
دور فلسفة الذكاءات المتعددة في تفعيل مفاهيم اليقظة الاستراتيجية - بحث وصفي تحليلي لآراء عينة من المدراء العاملين في وزارة الصناعة والمعادن
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تناول البحث أبعاد الذكاءات المتعددة كمتغير مستقل بأبعاده الفرعية الثمانية ( الذكاء الاجتماعي ،الذكاء الطبيعي، الذكاء البصري، الذكاء المنطقي، الذكاء اللغوي، الذكاء الموسيقي، الذكاء الحركي/الحسي، الذكاء الشخصي/ البيئي) واليقظة الاستراتيجية كمتغير تابع بأبعاده الفرعية الثلاثة ( اليقظة التجارية، اليقظة التنافسية ، اليقظة التكنولوجية) وقد تم اختيار عينة من المديرين العاملين في وزارة الصناعة والمعادن، فق

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Publication Date
Mon Apr 29 2019
Journal Name
Arab Science Heritage Journal
توظيف شخصيات التراث الديني في شعر أديب کمال الدين
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 Using religious characters which come from religion is a significant means that poets applied in their texts. The Iraqi poet Adib Kamal Aldin applied religious characters as an active means helping the theme of the text and playing a great role in expanding the meanings and their implications in the text. 

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