Geometry change impact on thermal efficiency with large volumetric sensible heat storage tank

Abstract

By installation in district heating and cooling systems, large volumetric sensible heat storage tank is a technology that can reduce CO 2 emissions into the atmosphere, ensure the integration of renewable energy sources into district heating and cooling systems, overcome the mismatch between production and demand and increase reliability and efficiency of entire systems. Such tanks operate on the principle of temperature stratification. In this paper, the processes of charging and discharging the heat storage tank used in district heating systems depending on the geometric and process parameters are analyzed and the thermal efficiency of each of these processes is calculated. The thermal efficiency of the tank charging process is calculated based on the distribution of the warmer water temperature in the tank after the complete tank charging process and varies between 53.85% and 96.75%. The thermal efficiency of the tank discharging process was calculated based on the warmer water outlet temperature and varies between 87.83% and 96.00%. Validation of mathematical model was achieved by comparing the data obtained by measuring the water temperature in the heat storage tank installed in the city thermal power plant-heat plant and the results of numerical calculation.