Automation of the heated floor system in a room under the influence of ambient conditions

Abstract

Energy consumption for cooling and heating buildings should be reduced in the future to maintain suitable indoor thermal comfort at a lower cost. Numerical simulation of heat transfer within building systems can help to design the energy-efficient buildings. This article presents a fundamental theoretical research done to understand the effect of automation of the underfloor heating system in a room under the influence of ambient conditions on heat transfer. The considered physical process has been described mathematically taking into account the turbulent natural convection and thermal surface radiation within an air filled enclosure having a panoramic window. Sinusoidal boundary condition has been applied to the external surface of panoramic window to model the possible diurnal ambient temperature oscillation. An automation of the underfloor heating system is determined by the heater volumetric heat flux that magnitude depends on the ambient conditions. The governing equations with boundary conditions have been solved numerically by the finite-difference method. The influence of the relevant parameters, viz., surface emissivity, length of underfloor heating system and ambient boundary conditions has been investigated in detail. Distributions of integral and local characteristics illustrating flow and thermal structures in the large-scale enclosure have been studied. The contribution of the thermal radiative mechanism to the overall heat transfer is close in magnitude to the convective heat transfer even under normal room conditions.