Dynamic calculation of thermal bridges

Thermal bridges play a relatively large role in heat loss with increasing thermal insulation level of building envelope. In this paper, multi-dimensional dynamic models are set up to predict the thermal performances of thermal bridges using a frequency response method. The thermal bridge is divided into finite meshes where the nodal temperatures are expressed in the form of complex quantities that are related to amplitude and phase lag of the variations of the temperature. By considering the heat balance for the nodes, the real and imaginary parts of the nodal temperatures can be solved simultaneously. A PC computer program has been developed to calculate the dynamic responses of temperatures and heat flows within thermal bridges, and has been utilized for thermal bridges such as a light weight metal stud wall, a heavy weight wall—intermediate floor junction and a wall foundation with ground coupling.