In the refrigeration and air conditioning fields, the needs of energy conservation and renewable energy spread have become stronger recently. In this study, we aim at the development of the heat driven type metal hydride (abbr, MH) that can be driven by the low temperature exhausted heat or solar heat under 100°C. In order to commercialize this system, the heat transfer characteristics and the activation characteristics of MH particle bed must be more improved, and production cost must be more reduced. In this study, we use the two heat transfer enhancement methods for improving the low effective thermal conductivity of MH particle bed. One is by heat pipe (abbr., HP) and another is by brush type carbon fiber. HP is inserted into heat source part MH (abbr., MH1). By this method, we aim not only to enhance the heat transfer of MH1 particle bed but also to achieve the temperature uniformity of MH1 particle one. The effective thermal conductivity of cooling part MH (abbr., MH2) particle bed is enhanced by inserting the brush type carbon fiber. The influence of these heat transfer methods on our MH refrigeration system is estimated by measurement and calculation.
Experimental Study on Heat Transfer Enhancement of the Solid Reactant Particle Bed in a Chemical Heat Pump Using Ca(OH)2/CaO Reaction.