Comparison between a new TRNSYS model and experimental data of phase change materials in a solar combisystem

In the framework of the IEA Task 32 (Solar Heating and Cooling Programme), we developed a numeric model to simulate heat transfer in phase change materials (PCM), and experimental data. The analyzed system is bulk PCM plunged in a water tank storage of a solar combisystem (heating and domestic hot water production). The numerical model, based on the enthalpy approach, takes into account hysteresis and subcooling characteristic and also the conduction and the convection in the PCM. This model has been implemented in an existing TRNSYS type of water tank storage.

Novel ventilation cooling system for reducing air conditioning use in buildings.

Night-time cooling of buildings is a recognized way of reducing the use of air conditioning, and hence energy consumption. The paper describes the construction and testing of a latent heat storage system, which uses a novel combination of night cooling, heat pipes and phase change materials (PCMs) and has the distinct advantage that it is suitable for fitting to existing buildings. The design of the heal pipe/PCM heat storage unit is briefly discussed.