Validation of thermocline storage model with experimental data of a laboratory-scale molten salt test facility

The Fraunhofer ISE single-tank simulation model was parameterized and inputs were set according to the Fraunhofer ISE lab-scale storage tank in order to validate the model. The measured stratification during the charging cycle was compared to the temperature distribution of the simulated storage tank. If the effective diffusivity factor was calculated according to literature correlations, it corresponded very well with the measurement data with a mean standard deviation of 1.21%. A parameter identification for the effective diffusivity factor of the storage was performed to reduce these deviations even further. It showed that the ideal effective diffusivity factor is 150. The mean standard deviation was further reduced to 1.14 %.