Modeling and Analysis for Mixed-Mode Cooling of Buildings

The study presents a transient thermal mode for the assessment of mixed-mode cooling in buildings with hybrid ventilation and high levels of exposed thermal mass. The model is based on the thermal network representation of a building that can capture the non-uniform form surface and air temperature distribution within a building space considering smaller simulation sub-zones. Advective heat transfer associated with airflow is used for computing the thermal exchange between air nodes in offensive sub-zones. Two-dimensional heat conduction is considered to describe the horizontal and vertical heal transfer within the massive floor slab: The model is validated with monitored data from weepier institutional building under real conditions. The beat removal from the building thermal mass by the cool air stream is close to 1.3 and 3.1 times higher with the air stream at an average temperature of 12 degrees C (53.6 degrees F) compared to that with an air stream at 15 degrees C (59 degrees F) and 18 degrees C (64.4 degrees F) respectively. The might cooling operation hours and the selection of low temperature set-point have a significant impact on the following day's cooling demand the cases considered. The simulation results indicate the necessity for developing optimal model-predictive control strategies Jiff buildings with mixed-mode cooling.