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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
Wed Jun 18 2025
Journal Name
دار اراء للطباعة والنشر والتوزيع
الصحة النفسية في عصر التكنلوجيا تحليل للتحديات والفرص المتاحة
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بكل تواضع، نقدم لكم هذا الكتاب بعنوان "الصحة النفسية في عصر التكنولوجيا: تحليل للتحديات والفرص المتاحة". يسعى الكتاب إلى إلقاء الضوء على العلاقة المعقدة بين عالمنا الرقمي المتنامي وصحة عقولنا وقلوبنا. نعيش في زمن يشهد تغييرات كبيرة نتيجة التقدم التكنولوجي، حيث أصبحت الأدوات الرقمية جزءًا أساسيًا من حياتنا اليومية، تؤثر في أساليب تواصلنا، تعلمنا، وتفاعلنا مع محيطنا. لذا، يصبح من الضروري فهم تأثير هذه التقنيا

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Publication Date
Sun Jan 02 2005
Journal Name
Political Sciences Journal
عرض اطروحة (الحركات الاسلامية في ظل الوضع الدولي الجديد)
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الحركات الاسلامية في ظل الوضع الدولي الجديد

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Publication Date
Tue Oct 20 2026
Journal Name
Journal Of Administration And Economics
مؤشرات مقترحة لتقييم الاستدامة المالية في الجامعات الحكومية العراقية
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Publication Date
Thu Nov 08 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
المشكالت الصحية المرافقة لالستخدام الخاطئ للحاسوب في مدينة بغداد
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The Research aimed for identification the significant of health problems that occurrences through
misused of computer for those whom attaches with more than two hours daily and to identification the
nature of demographical characteristics variables and that related variables with using computer. Also to
know the level of user’s knowledge for some attaché’s equipment's and finally creating a new suggested
measurement scale for studying health problems that were occurred through misused of computer.
Creating questionnaire includes several domains (Social problems – family environment, Social problems –
external environment, some health problems attaches with related equipment's, psychological problems,
and hea

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة بعض المقدّرات الحصينة في دوال التمييز بأستخدام المحاكاة
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The development in manufacturing computers from both (Hardware and Software) sides, make complicated robust estimators became computable and gave us new way of dealing with the data, when classical discriminant methods failed in achieving its optimal properties especially when data contains a percentage of outliers. Thus, the inability to have the minimum probability of misclassification. The research aim to compare robust estimators which are resistant to outlier influence like robust H estimator, robust S estimator and robust MCD estimator, also robustify misclassification probability with showing outlier influence on the percentage of misclassification when using classical methods. ,the other

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Publication Date
Tue Feb 02 2021
Journal Name
كلية القانون والعلوم السياسية
التنافس الامريكي الفرنسي في القارة الافريقية بعد عام 2000
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تعدُّ القارة الإفريقية ذات موقع جيوسياسي إذ إنه يربط دول العالم بعضها ببعض، وأنّها تحتوي على ثلث الاحتياط النفطي المؤكد العالمي واليوريانيوم والمعادن الأخرى مما جعلها ذات أهمية للدول العظمى، وأنّها غير مستقرة سياسياً إذ تكثر بها النزعات والهجمات الإرهابية مما جعل الدول العظمى تتسابق لوقف المشاكل، ومن أهم هذه الدول العظمى هي فرنسا التي تحتفظ بنفوذها السبق أي الاستعماري في القارة وأنّها لا تتنازل عنه لأي دو

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Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
مزار السيد القاسم بن الكاظم في بابل (تاريخه وعمارته)
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Among the imams who honor the soil of Iraq by embracing their remains is Imam Al-Qasim Ibn al-Imam Musa Ibn Ja'far ibn Muhammad ibn Ali ibn al-Hussein ibn Ali ibn Ali ibn Abu Talib, Amir of the believers Al-Kadhim (may peace be upon him ), the mother of the sons and the mother of his brother Imam Ali ibn Musa al-Rida (may peace be upon him), buried in the Holy QOM (1)It is one of the doors of need for Shiite Muslims All the stories of imams are similar in terms of injustice

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Publication Date
Tue Jun 03 2003
Journal Name
Al-academy
اسباب تفرد استخدام خط النسخ في تصميم الحروف الطباعية
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اسباب تفرد استخدام خط النسخ في تصميم الحروف الطباعية

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Publication Date
Tue Mar 15 2022
Journal Name
Arab Science Heritage Journal
الري والإصلاح الزراعي في العراق (1-132هـ/ 622-750م)
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The organization and development of the irrigation system and agrarian reform in Iraq had an impact on the diversity of its methods and uses

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Publication Date
Thu Oct 25 2018
Journal Name
Journal Of Planner And Development
تقويم كفاءة موقع النشاط التجاري في منطقة حي الاعلام
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