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Register a new userOptimization of a wall containing a Phase Change Material included in a metal matrix
الجدار الأمثل الحاوي على مواد متغيرة الطور (PCM) موضوعة ضمن هيكل معدني
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Tishreen University ورقة بحثية
Publication date
2017
fields
Mechanical Power Engineering
and research's language is
العربية
Authors
مها احمد( باحث )
Created by
Shamra Editor
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تلعب الجدران الحاوية على مواد متغيّرة الطور (PCM) دوراً مهماً في تكييف هواء الأبنية. لكن تُعتبر الإيصالية الحرارية الضعيفة للمواد متغيرة الطور بأنّها إحدى الخواص التي تحدّ من استخدامها. يمكن حلّ هذه المشكلة من خلال المزاوجة بين هيكل معدني مع المادة متغيرة الطور. هدف هذه الدراسة هو تحديد الأبعاد المثالية للجدار بحيث تسمح بتغيّر كامل للطور، و بمجانسة درجة الحرارة من دون أن يحصل تغيّر سريع في الطور. من أجل دراسة السلوك الحراري للجدار، قمنا بإجراء محاكاة رقمية باستخدام البرنامج ®COMSOL على خلية عنصرية. و من أجل وصف تغيّر الطور، استخدمنا طريقة السعة الحرارية المكافئة. اخترنا البارافين (الذي درجة حرارة انصهاره 24,5 °C) كمادة متغيّرة الطور. كما قمنا بتعيين تأثير كلّ من نوع معدن الخلية و النسبة الحجمية له. قمنا على وجه الخصوص بدراسة الهيكل المعدني الذي له بنية على شكل خلية نحل مصنوعة من الألمنيوم.
The walls containing phase change materials (PCM) play a significant role in the air conditioning of buildings. However, one of the characteristics which limits the use of PCMs is their low conductivity. It is possible to solve this problem by coupling a metal matrix with the PCM. The aim of this study is to determine the optimal size of a wall which allows a complete change of state, and a homogenization of the temperature without a too fast change-of-state rate. To study the thermal behavior of the wall, we have carried out a numerical simulation using the COMSOL® software in considering a unit cell. To describe the change of state, the method of the equivalent heat capacity has been used. Paraffin has been chosen as PCM (melting temperature 24.5 °C). The influence of the nature and the volume fraction of the metal were determined. The case of honeycombs made of aluminum has been specifically treated.
References used
KHUDAIR. A. M, FARID. M.M, A review on energy conservation in building applications with thermal storage by latent heat using phase change materials. Energy conversion and management, Volume 45, 2004, 263 – 275
HONG. S.T, HERLING. D.R, Effect of surface area density of aluminum foams on thermal conductivity of aluminum-foam-phase change material composites. Advanced Engineering Materials, Volume 9, 2007, 554-557
HONG. S.T, HERLING. D.R, Open-cell aluminum foams filled with phase change materials as compact heat sinks, Scripta Materialia, Volume 55, 2006, 887-890
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The objective of this investigation is to study the influence of application of phase
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The experimental results of this investigation showed that using phase change
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Also the experimental results of this investigation showed an increase in the period
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An application of these materials is thermal energy storage. The PCM integrated into
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PCM is their low conductivity.
The objective of this article is to propose a selection of materials having a
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the use of a PCM as a passive air conditioning system fits.
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choose certain materials.
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