Highly-turbulent packed bed heat exchange: modelling, experiment and validation

Abstract

SynchroStor Ltd. is developing a system for Pumped Thermal Energy Storage (PTES) based on the closed Brayton cycle principle. A numerical model of the gas-solid heat exchanger used by the cycle was developed in MATLAB to both evaluate the performance of the proposed arrangement and act as a design tool. A series of physical tests were run on a reduced-scale experimental test rig to assist with validation of the model. Thermal resistance due to radial conduction through the solid particles was found to be a critical feature of the model for SynchroStor’s design conditions; model outputs matched temperatures measured at each thermocouple station of the test rig with accuracies better than ±4.0%. The model was experimentally-validated for flows with superficial Reynolds numbers (Re) in the range 4,300 to 11,100.