Phase Change Material Melting in an Energy Storage Module for a Micro Environmental Control System

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Mustafa Koz ◽  
H. Ezzat Khalifa
Keyword(s):  
Control System ◽  
Energy Consumption ◽  
Thermal Comfort ◽  
Phase Change ◽  
Phase Change Material ◽  
Environmental Control ◽  
Design Parameters ◽  
Airflow Rate ◽  
Local Cooling ◽  
Change Material

Abstract An experimentally validated finite element model (FEM) was developed to analyze the design parameters of a latent heat storage device (LHSD) for a micro environmental control system (μX). The μX provides local cooling to an office worker in a room whose thermostat setpoint has been elevated from 23.9 °C (75 °F) to 26.1 °C (79 °F) in order to reduce heating, ventilation, and air conditioning (HVAC) energy consumption. For this application, the LHSD is designed to provide ≥50 W of cooling for a full, 8.5 h workday to restore thermal comfort in the warm, 26.1 °C room. The LHSD comprises several parallel slabs of encased phase change material (PCM) with interposed airflow channels. The airflow rate is selected to obtain ≥50 W of cooling at the end of the 8.5 h operation. The LHSD exhibits a decreasing cooling rate over the 8.5 h period when a constant airflow is passed through it, indicating that more cooling is supplied during the day than the minimum 50 W required for thermal comfort. The parametric analysis explores the effects of PCM thermal conductivity, slab thickness, air channel width, and number of slabs on LHSD performance. Parametric cases are compared against each other on the basis of their required PCM mass and energy consumption.

Sodium acetate–urea composite phase change material used in building envelopes for thermal insulation

2017 ◽  
Vol 39 (4) ◽  
pp. 475-491 ◽  
Author(s):  
Yin Zhang ◽  
Xin Wang ◽  
Zhiyuan Wei ◽  
Yinping Zhang ◽  
Ya Feng
Keyword(s):  
Energy Consumption ◽  
Thermal Comfort ◽  
Phase Change ◽  
Phase Change Material ◽  
Thermal Insulation ◽  
Sodium Acetate ◽  
Building Envelopes ◽  
Indoor Thermal Comfort ◽  
Composite Phase Change Material ◽  
Change Material

Integrating phase change material with building envelopes is an effective way to reduce cooling or heating loads, improve indoor thermal comfort and save building energy consumption. In this paper, the composite phase change material of sodium acetate and urea is prepared and its thermal–physical properties with different mixing mass ratios are investigated through experiment and T-history method. Moreover, the heat transfer model of building envelopes with phase change material is established and different phase change material locations in external walls for thermal insulation are compared based on integrated uncomfortable degree. The results show that (1) with rising urea mass fraction, both phase change temperature and latent fusion heat (enthalpy) decline; (2) strontium sulfate is an effective nucleating additive to decrease super-cooling degree for such phase change material solidification and (3) to improve indoor thermal comfort, it is preferable to put phase change material in the middle of external walls. Furthermore, the illustrative example of an office building in Chengdu indicates that phase change material insulation can lead to time lag and decrement for indoor air temperature variations. It also indicates that after inserting such phase change material into building external wall, the highest indoor temperature can be decreased by 7℃, leading to 60% cooling energy saving in one typical summer day. This work can provide guidance for building thermal design with phase change materials. Practical application:The studied sodium acetate–urea composite phase change material has been used as energy storage and thermal insulation materials inserted in envelopes for the demonstration project of low/zero energy consumption passive buildings in China.

scholarly journals Effect of phase change material using in building thermal comfort applications through several climate conditions.

2020 ◽  
Vol 170 ◽  
pp. 01007
Author(s):  
Marwa El Yassi ◽  
Ikram El Abbassi ◽  
Alexandre Pierre ◽  
Yannick Melinge
Keyword(s):  
Thermal Comfort ◽  
Phase Change ◽  
Phase Change Material ◽  
Phase Change Materials ◽  
Chemical Change ◽  
Thermal Inertia ◽  
Temperature Fluctuations ◽  
High Energy ◽  
Climate Conditions ◽  
Change Material

Nowadays, buildings sector contributes to climate change by consuming a considerable amount of energy to afford thermal comfort for occupants. Passive cooling techniques are a promising solution to increase the thermal inertia of building envelopes, and reduce temperature fluctuations. The phase change materials, known as PCM, can be efficiently employed to this purpose, because of their high energy storage density. Among the various existing solutions, the present study is dedicated to solid-liquid phase change materials. Temperature evolution (according to their defined temperature range) induces the chemical change of the material and its state. For building applications, the chemical transition can be accomplished from liquid to solid (solidification) and from solid to liquid (melting). In fact, this paper presents a comparative thermal analysis of several test rooms with and without phase change materials embedded in a composite wallboard in different climates. The used PCM consist in a flexible sheet of 5 mm thickness (Energain, manufactured by the company DuPont de Nemours). The main properties of such a commercial solution have been delivered by the manufacturer and from analyses. The room model was validated using laboratory instrumentations and measurements of a test room in four cities: Lyon; Reading and Casablanca. Results indicate that this phase change material board can absorb heat gains and also reduce the indoor air temperature fluctuations during daytime. The aim of the study is to show the benefits of this layer with phase change material and compare it in different climatic zones.

Red-mud geopolymer composite encapsulated phase change material for thermal comfort in built-sector

Solar Energy ◽  
2019 ◽  
Vol 181 ◽  
pp. 464-474 ◽  
Author(s):  
Lukmon Owolabi Afolabi ◽  
Zulkifli Mohamad Ariff ◽  
Puteri Sri Melor Megat-Yusoff ◽  
Hussain H. Al-Kayiem ◽  
Adiat Ibironke Arogundade ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Phase Change ◽  
Phase Change Material ◽  
Red Mud ◽  
Encapsulated Phase Change Material ◽  
Change Material

scholarly journals Influence of Thermal Insulation’s and Phase Change Material’s Insertion within a Partition Wall on the Energy Consumption of a Conditioned Room under Adjacent Local Periodical Temperature Effect

2020 ◽  
Vol 307 ◽  
pp. 01024
Author(s):  
Nisrine Hanchi ◽  
Hamid Hamza ◽  
Rabiaa Idmoussa ◽  
Jawad Lahjomri ◽  
Abdelaziz Oubarra
Keyword(s):  
Energy Consumption ◽  
Phase Change ◽  
Phase Change Material ◽  
Thermal Insulation ◽  
Phase Change Materials ◽  
Thermal Conditions ◽  
Thermal Activity ◽  
Partition Wall ◽  
Reduction Of Energy Consumption ◽  
Change Material

The aim of this work is to study the combined insertion effect of Phase Change Materials (PCM) and thermal insulation within a partition wall separating a conditioned room from an adjacent local which is under a periodic thermal activity. This is done by a comparative study with a reference wall under the same thermal conditions. The comparison criterion is the energy density transmitted to the local conditioned in established regime. The results show that the inclusion of thermal insulation and phase change material provides a significant reduction of energy consumption of the conditioned local; thereby a judicious choice of phase change material with thermal level and range melting temperature reduces further this reduction.

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