Empirical validation of a multizone building model coupled with an air flow network under complex realistic situations

Abstract

Building energy simulation (BES) assesses the energetic and thermal behaviour of buildings and can be used for the evaluation of energy conservation measures (ECMs). However, building modelling under realistic conditions can be challenging for simulation programs. The aim of this work is to test whether a multizone building model developed with a simulation tool can handle the complex situations of an in-use building. Monitoring data from the Twin Houses empirical validation experiment of the International Energy Agency, Energy in Buildings and Communities (IEA EBC) Annex 71 is used for that purpose. The multizone building model is developed with the energy simulation software TRNSYS coupled with an air flow network in TRNFLOW. The innovative aspect of this work lies in the validation of a combined multizone building model under stochastic occupancy gains, taking into account room-wise heating profiles, ventilation, and interior air flow currents due to window and door operation. The results of a coheating test showed that the errors in the simulated heating power for the whole house are a coefficient of variation of the root mean square error (CV(RMSE)) of 12.72% and a normalised mean bias error (NMBE) of −8.35%. Nevertheless, more difficulties were found in separately predicting the heating power of each individual room. However, the combined multizone air flow model was able to predict indoor temperatures in all rooms with root mean square error (RMSE) and mean absolute error (MAE) values of<1 °C.