Paper Conference

Proceedings of eSim 2006: 4th Conference of IBPSA-Canada



Qiu Kai, Fariborz Haghighat, Brian Coffey

Abstract: The breathing wall combines the air transferring through porous media and heat exchange, and also acts as an air filter. Therefore it has the advantage of supplying ventilation air to the building with less energy consumption. This paper presents an investigation into the thermal performance of buildings incorporating breathing wall elements, using the commercial software package TRNSYS. Annual energy consumption of the building, under an hourly changed environment temperature condition, is obtained. For the purpose of supplying guidelines for the implementation of breathing walls, simulations are performed under a range of air flow rates, with the variation of insulation thickness, as well as the ratio of breathing wall to normal wall. The simulation results show that energy consumption of building incorporated with breathing wall element is reduced due to the fact that the wall has been transformed into an air supplying ventilator and heat recovery device. The study also illustrates that the thermal performance of the breathing wall is directly influenced by air flow rate. For the whole range of air velocities in the simulation, which are 0.0002m/s to 0.00125m/s, the difference of energy saving extent is 6%~12%. The energy saving will be even smaller when considering the possible increase of fan power, because the pressure gradient is higher in the building with breathing wall. Therefore, to make the technique of breathing wall more applicable, further study is needed to combine this technique with natural ventilation.
Pages: 134 - 140