Preparation and Application of Paraffin/Expanded Graphite-Based Phase Change Material Floor for Solar-Heat Pump Combined Radiant Heating Systems

Abstract

Application of phase change material (PCM) floor as the thermal storage unit in a radiant heating system possesses the advantages of improving indoor comfort with high energy efficiency and favorable economic applicability. This work proposed a novel PCM floor by directly mixing the paraffin/expanded graphite composite PCM (CPCM) with building cements and then explored its practical application performance in a solar-heat pump combined radiant heating system. First, the mass fraction of CPCM was optimized, taking into account the thermal (thermal storage capacity, thermal conductivity, leakage analysis, thermal stability, and reliability) and mechanical properties (combined strength and flexural strength) that the PCM floor should have, and 35% was determined as the optimum mass fraction of CPCM for the PCM floor. Second, the application potential of the studied PCM floor was further evaluated by experimental measurements and TRNSYS simulations. The results showed that the thermal comfort satisfaction rate of the room based on the PCM floor reached 96.8%; by comparing the PCM floor room with the control one without a PCM layer installed in the floor, the enhancement of the PCM floor, that is, the indoor comfort improvement as well as the energy and economic impacts, was well interpreted.

Improving the charging rate and energy recovery of triplex tube heat storage-based pcm with mono/hybrid nanoparticles

“…Therefore, to resolve this problem, several techniques have been developed over the last few decades. These enhancement techniques involve using fins [5,6], heat pipes [7,8], highly conductive metal foam [9,10], nanoparticles [11,12], graphite composites [13,14], and carbon nanotubes [15,16].…”

Design of Crystal Growth Dimensionality in Synthetic Wax: The Kinetics of Nonisothermal Crystallization Processes

“…In the petroleum industry, the deposition of paraffin wax in crude tanks and pipelines affects flow efficiency at lower temperatures, increasing the demand for energy in transportation . On the other hand, wax crystallization is desired in the development of novel materials for energy storage in the energetics, electronics, and automotive industries. − Moreover, waxes exhibit a strong hydrophobic nature and are commonly used as water repellents, protective layers, and surface modifiers . Controlling wax crystallization is crucial in industrial processes of casting, injection molding, 3D printing, sensor materials design, and pharmaceutical applications. − For the reasons above, the exploration and modification of the crystallization behavior of waxes through various approaches become essential. − …”

“… 22 On the other hand, wax crystallization is desired in the development of novel materials for energy storage in the energetics, electronics, and automotive industries. 23 − 26 Moreover, waxes exhibit a strong hydrophobic nature and are commonly used as water repellents, protective layers, and surface modifiers. 27 Controlling wax crystallization is crucial in industrial processes of casting, injection molding, 3D printing, sensor materials design, and pharmaceutical applications.…”