Advanced Building Simulation

Air temperature (°C)
40.0
35.0
30.0
25.0
20.0
15.0
10.0
Air temperatures top floor
240.0
241.0
242.0
Onion 1/h
Onion 10/h
Ping-pong 1/h
Ping-pong 10/h
Ambient
Day of the year
243.0
244.0
245.0
246.0
Integrated building airflow simulation 105
it could be argued that in the current situation the results for the coupled solution
method with small time steps are the most accurate. This is why for each result the
percentage difference is shown relative to the results for the coupled solution with
10 time steps per hour.
Since the main interest here are the relative differences, no attempt has been made
to compare the case study results by intermodel comparison, for example with a
CFD approach, or to validate the outcome in an absolute sense by comparing with
experimental results.
A comparison with CFD results would not constitute a feasible option because
modeling of coupled building energy and CFD is still very much in its infancy
(Beausoleil-Morrison 2000; Zhai et al. 2002; Djunaedy et al. 2003).
Each of the decoupled building energy and airflow prediction methods have been
subjected to extensive and rigorous experimental validation exercises in the past
39.0
37.0
35.0
244.0 244.5 245.0
22.0
20.0
18.0
244.5 245.0
Day of the year
245.5
Figure 4.12 Simulation results for top floor air temperatures starting with day 241 and ending with
day 246 of a reference year. Frames on the right show selected results in more detail
(temperatures in �C).