Low temperature latent heat thermal energy storage: Heat storage materials

Thermal Regulation of Building-Integrated Photovoltaics Using Phase Change Materials

Numerical investigation of a PCM-based heat sink with internal fins

A review of phase change materials for vehicle component thermal buffering

Phase change materials (PCM) are characterized for storing a large amount of thermal energy while changing from one phase to another (generally solid-liquid states) at a specific temperature and presenting a high specific heat of phase change process. PCMs can be classified as organic, inorganic and eutectic. Such materials present some limitations, including subcooling, phase segregation, flammability, low thermal conductivity and thermal instability, among others. In order to overcome these problems, encapsulation of PCMs is being successfully developed, providing decreased subcooling, large heat transfer area, and controlling the volume change of the storage materials when the phase transition occurs. A considerable amount of studies has been published in the field of encapsulation methods for organic PCMs. Nevertheless, the information available on inorganic PCMs is scattered. Furthermore, the influence of the encapsulation techniques on thermophysical properties of PCMs is not reported in these reviews most of the time. Hence, the aim of this review is to summarize the encapsulation and characterization techniques for inorganic PCMs and to provide the analysis about the influence of synthesis parameters on thermophysical properties of encapsulated PCMs. Two principal types of encapsulated inorganic PCMs were found: core-shell PCMs (core-shell EPCMs) and shape stabilized PCMs (SS-PCMs). Classification of encapsulation methods of core-shell EPCMs and SS-PCMs are reported in this work. Among all the microencapsulation methods, inverse Pickering emulsion, electroplating, solvent evaporation–precipitation method and mechanical packaging are the most common methods described in the literature for the production of core-shell EPCM. On the other hand, for SS-PCMs, mainly sol-gel process, infiltration and impregnation encapsulation methods were found. Scientific works report a reduction in the heat of phase change for core-shell EPCMs. This is mostly because of the low content of salt in the final material. Moreover, an improvement of thermal conductivity was procured for SS-PCMs. Finally, PCM percentage, particle size, stirring rate, type of crosslinking agent and solvent properties were established as principal factors influencing the final properties of the encapsulated materials. For the best of our knowledge, this is the first profound review of encapsulation techniques for inorganic PCM.

A review on encapsulation techniques for inorganic phase change materials and the influence on their thermophysical properties

This handbook is intended to provide theory and data needed by the thermal design engineer to bridge the gap between research achievements and actual flight systems, within the limits of the current state of the art of phase change materials (PCM) technology. The relationship between PCM and more conventional thermal control techniques is described and numerous space and terrestrial applications of PCM are discussed. Material properties of the most promising PCMs are provided; the purposes and use of metallic filler materials in PCM composites are presented; and material compatibility considerations relevant to PCM design are included. The engineering considerations of PCM design are described, especially those pertaining to the thermodynamic and heat transfer phenomena peculiar to PCM design. Methods of obtaining data not currently available are presented. The special problems encountered in the space environment are described. Computational tools useful to the designer are discussed. In summary, each aspect of the PCM problem important to the design engineer is covered to the extent allowed by the scope of this effort and the state of the art.

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D. V. Hale

Papers

Phase-change materials handbook