Preferred Language
Articles
/
alkej-265
Experimental Study on the Effect of Insertion of Copper Lessing Rings in Phase Change Material (PCM) on the Performance of Thermal Energy Storage Unit
...Show More Authors

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Dec 08 2022
Journal Name
مجلة حمورابي
العقيدة العسكرية للمنظمات الارهابية الحرب اللامتماثلة في العراق عام 2014 انموذحا
...Show More Authors

Preview PDF
Publication Date
Wed Nov 28 2018
Journal Name
Arab Science Heritage Journal
جوانب جوانب من المعالجات البيئية والمناخية لعمائر الطين في الواحات الليبية
...Show More Authors

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

View Publication Preview PDF
Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
العامل العامل الاقتصادي وأثره في نشوء المدن الإسلامية وتطورها ( بخارى ) أنموذجاً
...Show More Authors

After atour-For quite somtime,in the field of research and investingation on the economic aspects and the impact of her money is mportantin the evolution and emegece of the Islamic countres,especially including especially Morkhana him specimer nigh borhood the countries of the mashreq al islami,searhout,among other things summarilesas

View Publication Preview PDF
Publication Date
Sun Jan 01 2017
Journal Name
المجلة القانونية العلمية المحكمة
الدور القانوني للحوافز الضريبية في تحقيق التراكم الراسمالي(العراق ومصر انموذجا)
...Show More Authors

Preview PDF
Publication Date
Tue Dec 27 2022
Journal Name
مجلة العلوم النفسية
متطلبات تطبيق الحوكمة في الجامعات العراقية جامعة بغداد - جامعة الانبار انموذجا
...Show More Authors

يعد النظام التعليمي لاي بلد انعكاسا للمستوى الثقافي والحضاري للمجتمع وعادة ما يحدد هذا النظام ويوجه من قبل التنظيمات السياسية والاقتصادية والاجتماعية في المجتمع كونها تعتمد علية في تحقيق اهدافها ,وصبحت الجامعة اليوم تمثل عمد النظام التربوي والتعليمي بما تمتلكه من كفاءات وقد ا رت وامكانيات بشرية ومادية تستطيع من خلالها رفد المجتمع بما يحتاجة من قد ا رت بشرية متعلمة في كافة الاختصاصات ومناحي الحياة لادامة ال

... Show More
Publication Date
Tue Aug 25 2026
Journal Name
مجلة العصر للعلوم الانسانية والاجتماع
موقف صحيفة الاهرام من الصراع في جمهورية الكونغو الديمقراطية 1964-1965
...Show More Authors

يتناول هذا البحث موقف ( صحيفة الاهرام) المصرية من تطورات الصراع في جمهورية الكونغو الديمقراطية خلال الفترة (1964 -1965) وهي مرحلة اتسمت باحتدام الازمات السياسية والنزاعات الداخلية في الكونغو مع زيادة التدخل الاجنبي في شؤون البلاد المتمثل بالولايات المتحدة الامريكية وبلجيكا وعلى هذا الاساس تم اختيار موضوع البحث والذي حددت بدايته بالتزامن مع عودة مويس تشومبي الى السلطة ، وما رافقها من صراعات وتمردات في الاقاليم

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2006
Journal Name
المركز العربي للدراسات والبحوث العلمية للنشر والتوزيع
القانون الجنائي في عصر الذكاء الاصطناعي :جرائم التزييف العميق تحت المجهر
...Show More Authors

مقدمة introduction تُعد تقنيات الذكاء الاصطناعي قاطرة الثورة الصناعية الرابعة، إذ تجاوزت حدود البرمجة التقليدية إلى التعلم العميق الذي مكّن الآلات من تنفيذ مهام بشرية معقدة، مثل تحليل الصور، ومعالجة اللغات الطبيعية، وإنتاج محتوى إبداعي. فأصبحت التطبيقات تعتمد على الذكاء الاصطناعي في جميع القطاعات، من الرعاية الصحية إلى التعليم، ومن الأمن إلى الفنون. ومع ذلك، مثلما أن كل تقدم يحمل في طياته إمكانات هائلة، فإنه يج

... Show More
Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Educational And Psychological Researches
Educational and psychological adjustment among hostel's students at Omer al-mokhtar University
...Show More Authors

Educational and psychological adjustment considered to be one of the effective and serious matters at people dealings and behaviors. Generally, psychological adjustment reflects positively on an individual mental health and their capability to be creative at their field. In contrast to those people who lack this feature. As for educational adjustment, it refers to the compatibility and harmony between an individuals and people around. Thus, these features should be available among students particularly those who stay in students' hostel since they live far from their families. The findings of study revealed that there is Educational and psychological adjustment between male and female. Besides, significant differences were showed

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 01 2020
Journal Name
Al-khwarizmi Engineering Journal
Applying Trade-off Curve to Support Set-Based Design application at an Aerospace Company
...Show More Authors

Companies compete greatly with each other today, so they need to focus on innovation to develop their products and make them competitive. Lean product development is the ideal way to develop product, foster innovation, maximize value, and reduce time. Set-Based Concurrent Engineering (SBCE) is an approved lean product improvement mechanism that builds on the creation of a number of alternative designs at the subsystem level. These designs are simultaneously improved and tested, and the weaker choices are removed gradually until the optimum solution is reached finally. SBCE implementations have been extensively performed in the automotive industry and there are a few case studies in the aerospace industry. This research describe the use o

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Wed Jan 11 2017
Journal Name
Journal: Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Characterization of some Metal Complexes with (3Z ,5Z, 8Z)-2-azido-8-[azido(3Z,5Z)-2-azido-2,6- bis(azidocarbonyl)-8,9-dihydro-2H-1,7-dioxa-3,4,5- triazonine-9-yl]methyl]-9-[(1-azido-1-hydroxy)methyl]-2H1,7-dioxa-3,4,5-triazonine – 2,6 – dicarbonylazide(L-AZ) .
...Show More Authors

The reaction of LAs-Cl8 : [ (2,2- (1-(3,4-bis(carboxylicdichloromethoxy)-5-oxo-2,5- dihydrofuran-2-yl)ethane – 1,2-diyl)bis(2,2-dichloroacetic acid)]with sodium azide in ethanol with drops of distilled water has been investigated . The new product L-AZ :(3Z ,5Z,8Z)-2- azido-8-[azido(3Z,5Z)-2-azido-2,6-bis(azidocarbonyl)-8,9-dihydro-2H-1,7-dioxa-3,4,5- triazonine-9-yl]methyl]-9-[(1-azido-1-hydroxy)methyl]-2H-1,7-dioxa-3,4,5-triazonine – 2,6 – dicarbonylazide was isolated and characterized by elemental analysis (C.H.N) , 1H-NMR , Mass spectrum and Fourier transform infrared spectrophotometer (FT-IR) . The reaction of the L-AZ withM+n: [ ( VO(II) , Cr(III) ,Mn(II) , Co(II) , Ni(II) , Cu(II) , Zn(II) , Cd(II) and Hg(II)] has been i

... Show More