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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 H NAT CV SF H

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 150 51 38 51 13
% of Hours 49% 17% 13% 17% 4%
NAT CV REC TEMP < 24 ºC 24 ºC - 27 ºC 27 ºC - 30 ºC > 27 ºC > 30 ºC
Number of Hours 142 52 40 58 18
% of Hours 56% 21% 16% 23% 7%

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).