Transient Behavior of a Solid Sensible Heat Thermal Storage Exchanger
The transient response characteristics of a solid sensible heat storage exchanger which interacts with two energy transporting fluids are presented. The storage unit is composed of a series of large aspect ratio rectangular channels for the fluids, separated by slabs of the heat storage material. The hot and cold fluids flow in counter current fashion, in alternate channels so that each slab of storage material is in contact with both fluids. The entire system is considered to be initially in equilibrium at a uniform temperature, a step change in the inlet temperature of one of the fluids is imposed, and the thermal response of the unit is predicted until steady state conditions are reached. The response of the storage exchanger to an arbitrary time variation of one of the fluids’ inlet temperature may be obtained using superposition.