Isothermal Airflow Characteristics in the Animal-occupied Zone of a Slot-ventilated Swine Facility

Airspeed and turbulence measurements were collected in a full-scale swine grower facility. Data were collected in three horizontal planes at eight axial locations from the inlet sidewall. Three inlet slot heights (20, 40, and 60 mm) and two fan stages resulted in six ventilating conditions investigated. The resulting 2x3 x 8 factorial experiment showed that fan stage, inlet height, and axial position from the inlet significantly affected (p < 0.01) airspeed variations in the animal-occupied zone (AOZ). Correlations between the AOZ and a convenient measuring plane (MP) were sought. AOZ airspeed was highly correlated with MP airspeed (rxy = 0.91). AOZ turbulent intensity (r^ = -0.51) and turbulent kinetic energy (r^ = 0.75) were moderately correlated with MP airspeed. AOZ turbulence levels were not correlated with MP turbulence levels. A procedure, consistent with the system characteristic technique, is proposed for predicting axial variations in AOZ airspeed. The technique can be used to assess AOZ airspeed levels relative to penning layout and ventilating conditions.