Numerical Heat Absorption Efficiency Comparison In The Application Of Phase Change Materials (PCM) On A Masonry Wall

This study researches the effect of phase change materials (PCMs) containing carbonized rice husks (CRHs) in wood plastic composites (WPCs) as roof finishing materials on roof-surface and indoor temperatures. A cool roof miniature model was prepared, and measurements were taken using three fixed temperatures of 30 to 32 °C, 35 to 37 °C, and 40 to 42 °C. Sodium sulfate decahydrate (Na2SO4·10H2O) and paraffin wax were selected as the PCMs. CRHs were used as additives to improve the thermal conductivities of the PCMs. At lower fixed temperatures such as 30 to 32 °C and 35 to 37 °C, the rates of increase of the surface temperatures of roofs containing CRHs with Na2SO4·10H2O, and paraffin wax, were observed to gradually decrease compared to those of the roofs without PCMs. The indoor temperatures for the above-mentioned PCMs containing CRHs were maintained to be lower than those of the indoors without PCMs. Additionally, as the CRH content in the PCM increased, the rates of increase of the roof-surface and indoor temperatures decreased due to a faster roof heat absorption by PCMs through the improved thermal conductivity of CRHs. However, under higher artificial temperatures such as 40 to 42 °C, Na2SO4·10H2O with CRHs exhibited no effect due to being out of latent heat range of Na2SO4·H2O. For paraffin wax, as CRH content increased, their roof- surface and indoor temperatures decreased. Especially, the surface temperature of the roof containing paraffin contained 5 wt.% CRHs reduced by 11 °C, and its indoor temperature dropped to 26.4 °C. The thermal conductivity of PCM was enhanced by the addition of CRHs. A suitable PCM selection in each location can result in the reduction of the roof-surface and indoor temperatures.

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Phase Change Material Used for Masonry Joints: Numerical Simulation and Scale Test

Proceedings ◽

10.3390/proceedings2019034016 ◽

2019 ◽

Vol 34 (1) ◽

pp. 16

Author(s):

Jiang ◽

Liu ◽

Yuan

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Phase Change ◽

Phase Change Material ◽

Phase Change Materials ◽

Masonry Wall ◽

Wall Structure ◽

Thermal Coefficient ◽

New Form ◽

Change Material

In order to effectively improve the thermal performance of the thermal insulation masonry wall, the thermal bridge effect of the grey joint on the heat transfer of the wall structure was studied. A brand-new form of phase change material walls, which used phase change materials in the wall parts to build ash joints, was carried out. The application of phase change material mortar, which was different from conventional "Hamburger" phase change material walls, was demonstrated to be a useful tool to reduce the thermal coefficient of the masonry wall. Furthermore, the scale-down test and numerical simulation of the heat transfer coefficient of the phase change material wall with different distribution of ash joints were experimented and discussed, and the feasibility of the new-form phase change material wall within the error range was verified.

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Possible applications of phase change materials in passive solutions of masonry wall elements

Journal of Civil Engineering Environment and Architecture ◽

10.7862/rb.2014.96 ◽

2014 ◽

Vol XXXI (61 (3/II/14)) ◽

pp. 297-306 ◽

Cited By ~ 1

Author(s):

Joanna Krasoń ◽

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Masonry Wall

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Heat Absorption and Release Characteristics on Heat Storage Walls with Different Materials

E3S Web of Conferences ◽

10.1051/e3sconf/201913602029 ◽

2019 ◽

Vol 136 ◽

pp. 02029

Author(s):

HU Haowei ◽

CHEN Xiaonan ◽

FANG Tingyong ◽

ZHU Mingjun

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Heat Storage ◽

Temperature Fields ◽

Heat Absorption ◽

Ansys Software ◽

Conservation Of Energy ◽

Storage Performance ◽

Low Energy Consumption ◽

Wall Materials

To analyze the storage performance of the envelope structure, based on the law of conservation of energy, the ANSYS software was employed to perform thermal analysis on three conventional wall materials and phase change materials, and the temperature fields and minimum temperature difference of the walls with different materials were obtained. The heat absorption and release characteristics of different wall materials were studied. Comparing the heat absorption and release characteristics of phase change materials, it was concluded that the phase change materials had better heat storage capacity, which provided a basis for promoting and developing low energy consumption technologies for buildings.

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Development of Inorganic Impregnated Phase Change Material(PCM) in the Pores of Activated Carbon

Journal of Korean Society of Environmental Engineers ◽

10.4491/ksee.2021.43.12.709 ◽

2021 ◽

Vol 43 (12) ◽

pp. 709-718

Author(s):

Soyoung Baek ◽

Yasaman Ghaffari ◽

Jiyeol Bae ◽

Kwang Soo Kim

Keyword(s):

Activated Carbon ◽

Phase Change ◽

Phase Change Material ◽

Phase Change Materials ◽

Dilution Method ◽

Nitrate Hexahydrate ◽

Heat Absorption ◽

Dilution Ratio ◽

Removal Method ◽

Change Material

Objectives : Recently, energy-related research has shifted from developing alternative energy to the efficient management technology of the produced energy. As an alternative, research on phase change materials (PCMs) capable of absorbing and releasing heat as an energy medium has been conducted. This study developed a more efficient heat storage medium using activated carbon as a medium for the phase change material. At the same time, we developed a method for efficiently impregnating the phase change material into the activated carbon pores.Methods : The activated carbon used in this experiment was charcoal powder activated carbon (250-350 mesh) and granular activated carbon. The inorganic phase change materials used in the experiment was manganese nitrate hexahydrate. The method for impregnating the phase change material was pressurization method and dilution method. The heat absorption / emission capacity of the developed material was examined within the range of 10℃ to 50℃.Results and Discussion : The Scanning electron microscope (SEM) and Transmission electron microscopy energy-dispersive X-ray spectroscopy (TEM-EDX) analysis showed that the phase change material was filled in the pore of activated carbon. When the phase change material is filled by the pressurized method, the material properties of manganese nitrate hexahydrate are reflected, resulting in absorption and release of heat at each phase change temperature. As a result of experiments for the selection of the optimum solvent in the phase change material filling study using the dilution method, when ethanol was used as the solvent, the heat absorption was clearly observed even after the phase change material was loaded. As a result of selecting the optimal dilution ratio, the ratio of ethanol was determined to be 1:1 as the dilution ratio with the lowest amount of floating activated carbon. The optimal solvent removal method experimental results show that the heat absorption/release section occurred when the ethanol was removed by evaporation at 85℃ temperature.Conclusions : 1) Both the pressurization method and the dilution method are filling methods in which inorganic phase change materials can be immobilized inside activated carbon, and heat absorption and release characteristics are maintained even after loading. 2) The heat absorption release was maintained for ethanol and the optimal dilution ratio was 1:1. 3) In case of the dilute solvent removal method, the heat absorption/release capacity was maintained when the solvent was removed using only the vaporization method.

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