Experimental and theoretical investigations of solidification and melting of ice for the design and operation of an ice store

The Institute for Thermodynamics and Thermal Engineering (ITW) of the University of Stuttgart has developed a novel solar powered 10 kW absorption chiller. This chiller was implemented in the cooling system of the instituteʹs building. To achieve a higher efficiency of the cooling system and to extend the hours of operation, a small ice store was designed, constructed and experimentally investigated. The experimental investigations include charging and discharging processes at different inlet temperatures and for different heat exchanger areas. For theoretical investigations a simulation program was developed and validated. Based on the results of these investigations a final heat exchanger design was established. In a further step the ice store was integrated into the buildingʹs cooling system. Long term measurements of the cooling system have shown good in-service behaviour of the ice store which fits the specific requirements of the cooling system in combination with the absorption chiller quite well.