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
Sun Jan 01 2017
Journal Name
مجلة الدنانير
تعزيز الممارسات الفردية والجماعية لتحقيق متطلبات راس المال المعرفي في جامعة بغداد
...Show More Authors

ب

Publication Date
Fri Feb 10 2023
Journal Name
مجلة دراسات في التاريخ والآثار
رؤى اقتصادية ومالية لابن أبي زرع الفاسي (ت741ه) في كتابه الأنيس المطرب
...Show More Authors

 There are many economic and financial visions that were mentioned in the book (Al-Anis Al-Mutreb in Rawd Al-Qirtas in the News of the Kings of Morocco and the History of the City of Fez). As this valuable book includes between its two covers, narrations that reveal important and pioneering events and practices that took place and were applied in the recent past on the scene of the countries of the Maghreb. This prompted the officials in the Marinid state to take quick measures to address and confront what happened.      Despite the large number and severity of these repercussions and interactions, it is not the nature of this research to download texts and visions beyond what they can bear, but

... Show More
View Publication Preview PDF
Publication Date
Tue Oct 11 2022
Journal Name
College Of Islamic Sciences
Hanbali's approach to building long and short travel provisions with issues attached to their provisions
...Show More Authors

 

The problem with research lies in hiding the Hanbali approach in building long and short travel provisions, as well as hiding some provisions relating to short travel that are not provided for by the jurists of Hanbali (in their books).

The research aims to demonstrate the approach and standards on which they based the long and short travel provisions, as well as to reflect the provisions of some of the issues that are silent on long and short travel, with evidence and significance.

The research included a preface and two researches, the researcher in the preface talked about the reality of long and short travel, in the first research on the approach of ha

... Show More
View Publication Preview PDF
Publication Date
Sat Sep 26 2026
Journal Name
Arab Scientific Heritage Journal
الجــانــب الإعــلامــي لخـطـبـة السيّدة زينب (عليها السلام) في الكوفة سنة 61هـ/684م
...Show More Authors

View Publication
Publication Date
Sun Jan 13 2019
Journal Name
Arab Science Heritage Journal
زين الدين الشماع الحلبي والتعريف بكتابه (سر الأسرار في معرفة الجواهر والأحجار)
...Show More Authors

عُني العرب منذ القدم بإستعمال الجواهروالأحجار الكريمة ، وإزدادت هذه العناية على مر العصور ، فقد إستعملوا الحلي المتنوعة ، والملابس المطعمة بالجواهر والأحجار الكريمة .

View Publication Preview PDF
Publication Date
Tue Jun 03 2003
Journal Name
Al-academy
التسليات في البلدان الاسلامية مشاهد حياة الطرب والالات الموسيقية كما يعكسها الفن
...Show More Authors

التسليات في البلدان الاسلامية مشاهد حياة الطرب والالات الموسيقية كما يعكسها الفن

View Publication Preview PDF
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
...Show More Authors

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
...Show More Authors

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. 

... Show More
View Publication Preview PDF
Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
وجوه من وجوه الاعجاز البلاغي في القرآن الكريم الايجاز (جوامع الكلم أنموذجاً)
...Show More Authors

 

        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

... Show More
View Publication Preview PDF
Publication Date
Sun Apr 06 2014
Journal Name
مجلة البحوث التربوية والنفسية
الذكاء الروحي لدى عينة من طلبة جامعة بغداد في ضوء بعض المتغيرات
...Show More Authors

هدف البحث التعرف على الذكاء الروحي لدى عينة من طلبة جامعة بغداد فضلا عن التعرف على الفروق بين الطلبة في الذكاء الروحي وفق متغير النوع ( الذكور- الإناث) ، ومتغير التخصص الدراسي ( علمي – إنساني) ومتغير المرحلة الدراسية ( المرحلة الأولى-المرحلة الرابعة) تألفت عينة البحث من (300) طالباً وطالبة ، وتم تطبيق - مقياس الذكاء الروحي وهو ( من إعداد الباحثة) ، وقد اسفرت نتائج البحث عن:--إن طلبة جامعة بغداد( عينة البحث) تمتعوا بمست

... Show More
View Publication Preview PDF