Industrial buildings represent a substantial portion of building energy consumption throughout the U.S., with heating, ventilation and air conditioning (HVAC) making up approximately 9.3% of net electricity and 6% of natural gas consumption. One of the main drivers of operation and energy use of the HVAC system is infiltration. For industrial buildings, many have a substantial number of large openings for shipping and receiving, often with these doors remaining open for extended period of time. Opportunities to reduce infiltration through these openings exist, such as through the use of air or plastic curtains. However, the relative energy savings impact of the such retrofits is not standardized in part because the baseline level of unconditioned air flowing into the existing large openings is not well established. This study examines wind speed variations impact on air infiltration rates within a large opening in an industrial-style building through experimental testing, in an effort to establish an empirical relationship between weather station wind speed and the wind-driven air flow experienced through large openings. Wind speed measurements were collected from multiple sensors installed at the opening and compared with data from a nearby weather station. Results show that wind speeds at weather station height (~10 m) level (4.75 m/s) were significantly higher than those at the opening (0.72 m/s), with the lowest sensor within the opening recording the highest wind speeds. Results also suggest that compared to the estimated wind speeds based on the existing EnergyPlus Effective Area Infiltration model, air speeds measured at the large opening were 60.9% lower. A data-driven regression model was then developed to estimate wind speed at the opening based on weather-station height wind speed data, achieving an R2 of 0.75, with cross-validation confirming its reliability. The resulting data-driven model can be used to better estimate the air speeds and thus infiltration experienced at large door openings, improving the overall ability of existing models to estimate energy implications of large door openings.
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