Abstract:
Thermal storage with molten salt is considered to be an important subsystem for solar thermal
power plants due to the fluctuation of sunshine over time. A molten salt thermal storage tank, in
which the fluid is stratified in temperature with hot in the upper and cold in the lower level due
to the density difference of the fluids. Generally porous media are used to fill the tank in order to
reduce the inventory of the molten salt and manage the mixing between the hot and cold molten
salt, so as to form a stable layer of thermocline. However, in the flow of molten salt, either the
hot fluid displaces the cold one or vice versa, phenomena of viscous fingering and/or channeling
are likely to occur, which may disturb the stability of the thermocline, resulting in an over
widened temperature transitional zone. In this study no porous media is used. The cold and the
hot fluid zone are in direct contact. In this work is studied the analysis of the flow when cold
molten salt displaces hot molten. Special attention is given to the thermocline region. Numerical
simulation is presented where are find to be useful for the process analysis, for the scale-up of
the thermal storage system and to evaluate the system reliability for industrial plants |
