Paper Conference

Proceedings of SimBuild Conference 2012: 5th conference of IBPSA USA


Conduction Transfer Functions in TRNSYS Multizone Building Model: Current Implementation, Limitations and Possible Improvements

Benoit Delcroix, Michaël Kummert, Ahmed Daoud, Marion Hiller
École Polytechnique de Montréal, Dept of Mechanical Engineering, Montréal, QC, Canada
Laboratoire des Technologies de l’Énergie, Hydro-Québec Research Institute, Shawinigan, QC, Canada
Transsolar Energietechnik GmbH, Stuttgart, Germany

Abstract: The Conduction Transfer Function (CTF) method is used by many building energy performance simulation programs to calculate 1-D transient heat conduction through multi-layer envelope components. TRNSYS is one of these programs, and several authors have reported problems with the current CTF implementation in its multizone building model, known as Type 56. Reported problems are related to heavy and highly insulated slabs and short time-step simulations (less than 15-minute time-step). This paper documents the current implementation of CTF in Type 56. It then reports on our investigation of some issues with the current implementation and their causes. Workarounds and short-term solutions are assessed and longer-term improvements are discussed.
Pages: 219 - 226