Methodology for the Evaluation of Natural Ventilation in ... - Cham

Figure 15. HOBO® H8 Series Temperature and Relative Humidity Data Logger Locations in aSample Half Floor Area. The black squares represent the thermocouple locations. This layout isduplicated in each of the four half floor plates.External conditions were recorded to provide data both on the conditions to which the buildingwas exposed and on the entering air properties. As there was a substantial amount of glazing onthe façades of the building (46 percent of the total façade area) solar radiation was an importantcondition to be monitored. Not only outside air temperature, but also humidity, barometricpressure, direct and diffuse solar radiation, and wind speed were recorded. A Campbell Scientificweather station using a CR10X data recorder was mounted on the roof of the prototype building.The weather station was located so that it would not be influenced by exhaust air from the stackvents, nor sheltered from the outside elements. The outside temperature gauge was housed in awhite plastic device so that it was not subject to erroneous readings due to solar gain, rain orwind. The rotating vane cup anemometer was located 1 meter above the atrium roofline,approximately 1.5 meters away from any stack vent. The program used to record the datameasured the gusting or peak wind speed over the fifteen-minute interval as well as the averagevalue over the same interval. Both direct and diffuse solar radiation was measured using theweather station. The solar radiation data was recorded by using one pyranometer for thehorizontal solar radiation, and another pyranometer along with a shadow-band device thatrecorded diffuse solar radiation. The shadow-band rotated to shade the direct solar radiation tothe pyranometer, while recording the diffuse solar radiation.3.3.1.2 Air Quality MeasurementsEvaluating the ventilation performance of naturally ventilated buildings is more complex thanthe evaluation of a mechanically-conditioned building. The environment within the naturallyventilated building is affected not only by changes in the outside environment, e.g. wind speedand direction, but also by occupant behavior. In the prototype building, the main windows areoccupant controlled and can be anywhere from cracked open to fully opened, 0.24 meters in thehorizontal direction. The window geometry was an additional factor that had to be addressed in49