Author(s)

N. Penkova, N. Harryzanov

Abstract

A mathematical model of the transient temperature and fluid flow fields in the multiphase domain at a water thermal energy storage tank is composed. The model is applied for an analysis of the transport phenomena at the heat storage accumulator, charged by waste heat flows of a cogeneration unit and discharged by thermal energy supply to the heating installation of a conservatory. Numerical investigations of the transient 3D temperature and fluid flow fields in the accumulator at different charging and discharging regimes have been performed in order to estimate the temperature variations of the outflows, situated at different levels. Recommendations for the improvements of the design and the operation of the accumulator are formulated to ensure higher temperature stratification in the water domain and subsequent continuous and smooth work of the CHP and heating installations.

Keywords

thermal energy storage, temperature stratification, CFD, turbulence model, operation