A Superposition Method to Predict Indoor Temperature Distribution with Convective Heat Gain/Loss Through the Building Envelope

Abstract

Conventionally, indoor temperature is non-uniformly distributed and it is important to predict the distribution of temperature when working space must be controlled. The prediction based on the linear superposition theorem in a fixed flow field is an alternative with consideration of both efficiency and accuracy. However, indoor temperature distribution is not clearly investigated when convective heat transfer from the building envelope exists since the indoor temperature is coupled with heat transfer process. In this study, a method is proposed to predict the indoor temperature distribution where convective heat transfer from the boundary exists based on superposition theorem. Two representative flow fields in the room, i.e., one for space-cooling and one for space-heating, are selected for comparison. The characteristics of the two flow fields are analyzed by using two factors k₁ and k₂. Results show that: (1) there is a linear relation between excess temperature distribution, excess supply air temperature and heat source intensity; (2) the steady temperature can be predicted fast and accurate once k₁ and k₂ are obtained through simulations of two arbitrary thermal cases; (3) The proposed method could predict the indoor temperature distribution with good accuracy compared with numerical method.