Numerical and experimental evaluation of ice storages with ice on capillary mat heat exchangers for solar-ice systems

Four capillary mat heat exchangers set-ups have been experimentally evaluated using two volume flow rates and several testing sequences, i.e. sensible and cooling, icing and melting. An ice storage model with capillary mat heat exchangers able to consider the solidification of ice for asymmetric tube configurations has been developed and validated with the experiments. The model showed good results with root mean square (RMS) energy differences around 2% for sensible heating and cooling and was able to predict the solidification of ice well for both symmetric and non-symmetric configurations with energy RMS differences of 6%. Differences in sensible heating and cooling, and in the solidification process, were in general in the same order of magnitude for varying volume flow rate and tube spacing in the two dimensions. Differences of the melting process were found to be more dependent on the tube spacing and volume flow rates.