Theoretical and experimental investigation of the efficiency of the use of heat-accumulating material for heat supply systems

Abstract

As a result of research, the conditions for the effective use of the volume of heat accumulator based on solid materials were determined. In the course of research, various schemes of the device of tubular heating elements for charging the channel elements of the heat accumulator were considered. Fire clay was used as a heat-accumulating material, capable of operating in a wide temperature range (up to 600 °С). Mathematical modeling of temperature change in the process of discharge over the cross section of the heat-accumulating unit has been carried out. Mathematical modeling was carried out using an application package that allows to obtain the temperature distribution over the cross section of the heat accumulator at key points of its work. The obtained simulation results were tested on an experimental setup consisting of four heat-accumulating units during the charging process and during the discharge of the heat accumulator. According to the research results, the most effective layout of the heating elements was determined, which allows to make the most of the volume of the heat-accumulating material. The dependencies to determine the exponent and the averaging coefficient of the heat flux are also found, which allow a more rational use of the volume of the accumulating nozzle. The research results can be used to reconstruct decentralized heat supply systems for both residential buildings and public buildings. This will significantly align the schedule of electricity consumption during the day and reduce the consumption of hydrocarbon fuels.