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Case Name Airflow Flow Pattern Cooling Source EnergyPlus
Input file		 Spreadsheet
Results File
NAT CV Natural Cross-Vent. Natural NAT CV SF L NAT CV SF L

Description

In this case the single zone office building will be cooled using natural cross-ventilation. Ventilation openings are located in the North and south façade. The windows are open during working hours.

Cooling Strategy

Outside air is used to remove heat from the building in a cross-ventilation configuration.

EnergyPlus Models Used

Cross-Ventilation model (UCSD Cross Ventilation).

COMIS (wind driven airflow).

Simulation Results

NAT CV JET TEMP < 24 ºC 24 ºC - 27 ºC 27 ºC - 30 ºC > 27 ºC > 30 ºC
Number of Hours 169 49 26 34 8
% of Hours 67% 19% 10% 14% 3%
NAT CV REC TEMP < 24 ºC 24 ºC - 27 ºC 27 ºC - 30 ºC > 27 ºC > 30 ºC
Number of Hours 158 54 30 40 10
% of Hours 63% 21% 12% 16% 4%

Analysis

In the results obtained for this case the containment effects generated by the recirculation flow are clearly visible in the higher temperatures predicted for this region.

While temperature may be lower in the jet region of the flow the predicted airflow velocities are higher and may be incompatible with paperwork.

This first configuration is the least effective of the six cooling strategies analyzed (higher number of overheating hours, see result summary).