Paraffin/porous-graphite-matrix composite as a high and constant power thermal storage material

In recent years, storage of thermal energy has become a very important topic in many engineering applications and has been the subject of a great deal of research activity. This paper reviews the thermal energy storage technologies suitable for building applications with a particular interest in heat storage materials. The paper provides an insight into recent developments on materials, their classification, their limitations and possible improvements for their use in buildings. Three major thermal energy storage modes (sensible heat, latent heat, thermochemical heat) are described emphasizing the main characteristics of the most suitable heat storage materials for each.

A review of potential materials for thermal energy storage in building applications

Adsorption refrigeration- : An efficient way to make good use of waste heat and solar energy

Solid sorption refrigeration is a type of environmental benign and energy saving technology and the sorbents utilized can be divided into physical, chemical and composite sorbents, according to the nature of the forces involved in the adsorption process. The types, characteristics, advantages and disadvantages of different adsorbents, refrigerants and working pairs are summarized in this paper, together with the models that describe the adsorption equilibrium. Moreover, some of the procedures to prepare composite adsorbents are presented. The application of different working pairs for different situations is related with the adsorption heat, the adaptability to the driving temperature and to the desired working pressure. The methods to measure the adsorption quantity of different working pairs are compared, and future research directions of adsorption working pairs are also analyzed.

A review on adsorption working pairs for refrigeration

Effect of carbon nanofiber additives on thermal behavior of phase change materials

The method used to fill a chemical heat pump reactor with its porous reactive medium governs the heat and mass transfer in the reactor and hence its performance in terms of heat, power and capacity. The filling operation consists of mixing the salt, which takes place in the solid-gas reaction, and an inert graphite binder, and in confining this mixture to obtain a given apparent density. Depending on the binder properties and the mixing technique, the values (experimentally obtained) of the effective conductivities, λe, of the heat transfer coefficients, hsw, at the exchanger wall and of the permeabilities, k, cover a very large range: 0.2 W m −1 K −1 ⩽λ e ⩽40 W m −1 K −1 15 W m −2 K −1 K −1 ⩽h sw ⩽15,000 R m −2 K −1 , 0.03 × 10 −12 m 2 ⩽k⩽30 × 10 −12 m 2 . For some simple cases in which one limitation predominates over all the others, a simple relation has been set up between the reactor's power output per unit volume and a single filling parameter.

F L'Haridon

Papers

Heat and mass transfer in consolidated reacting beds for thermochemical systems