Ice formation modelling around the coils of an ice storage tank

Abstract

This paper aims to develop a dynamic model of the charging process of a commercial ice-storage tank. Firstly, three different 1st order and 2nd order numerical schemes have been compared to solve the transport equation of the heat transfer fluid. Euler's method has finally been chosen as the mass flow rate can vary throughout the charging and it avoids the oscillations which are introduced by Lax-Wendroff's and MacCormack's method. Secondly, the heat transfer outside the coils is analyzed. The numerical complications involved in the creation of the first ice layer around the tubes are discussed and an electrical resistance model is introduced to avoid this problem. The model results have provided a very good agreement with experimental measurements of charging tests which have been performed on a CALMAC ICEBANK tank with a capacity of 172 kWh. The model helps to predict the final part of the latent heat transfer process, where the thermal power is decreased due to the contact between the ice layers around adjacent tubes of the tank. © Published under licence by IOP Publishing Ltd.