Validation of a Zonal Model to Capture the Thermal Stratification in a Room Heated by a Stove

Abstract

Using wood stoves is a common space-heating strategy in the Nordic countries. The power oversizing of a stove for a given building might deteriorate the indoor thermal environment, for instance with large thermal stratification. This thermal environment is difficult to model and, in practice, a simple modelling approach is needed with acceptable accuracy and computational time. The aim of this study is to validate a zonal model against experiments conducted in a test cell laboratory, which was heated using an electric stove mimicking real wood stoves. The model combines the Togari zonal model, the standard plume theory and detailed modelling of longwave radiation between internal surfaces in the zone. The transient model managed to well reproduce the time evolution of temperatures, the vertical air temperature profiles and the internal surface temperatures. The present test case required the assumption of a constrained plume due to the small dimensions of the room. However, in reality, installing a wood stove of several kilowatts in a small room is unlikely and a free plume is a better candidate for real life applications. In addition, stoves are usually placed near walls and in the future it is important to characterize the plume interaction with vertical walls.