Abstract
Diseases and the hygiene of livestock are major concerns in the animal industry. Pathogens or virus aerosol spread by airflow, and it is therefore essential to understand the dispersion of contaminants and transfer between livestock buildings. The aim of this study was to investigate contaminant invasion from a gas emitting room to other rooms and the contaminant dispersion properties from the emitting building. To achieve these aims, wind tunnel model experiments under non-isothermal, steady state conditions were performed for an enclosed, two layer flat floor broiler house. Ethylene gas was used as a contaminant.
The contaminant quantity of the invaded rooms was significantly influenced by the contaminant emitting location and the separation distance between the windward building and the leeward building. When the emitting room was the ground floor in the windward building and the separation distance was 4 × H (ridge height), the quantity of contaminant invading the rooms was the smallest, less than a level of 10-3 to the generated rate. The contaminant could be transferred into the windward building even though the emitting building was the leeward building and the transferred quantity was larger at 10-2 order to the generated rate than that when the emitting building was the windward building. Likewise, the outside contaminant dispersion property was significantly affected by the emitting location and separation distance. The average dispersion intensity below 2 times ridge height was the smallest at 0.095 when the emitting room was the ground floor in the windward building and the separation distance was 4 × H.
