Abstract
In the self-evaporation process of hot water in a vertical steam accumulator, the mean temperature of hot water in the vessel is higher than the saturation temperature corresponding to the operation pressure. This temperature deviation generates a capacity loss of a thermal storage system, and should be reduced by optimal designs of internal baffles. In this study, hot water circulation, that is naturally and permanently induced by self evaporation, is analytically studied on an assumption and a simplification as follows. (1) single straight tube is used as the internal baffle, (2) steam and hot water in the two phase flow are in the thermal equilibrium condition. Analysis results show that the solution obtained agree well with visual test results. By using this analysis method, temperature deviations in hot water layer were estimated for various accumulators having wide range of operation conditions, volume and aspect ratio of the vessel.
