USING SWINE DUST TO VERIFY A LUMPED-PARAMETER MODEL IN A VENTILATED ENCLOSURE

Swine dust was used as a test dust to verify a lumped-parameter model derived for predicting airborne dust concentrations at any location wi thin a ventilated airspace. Average equilibrium airborne dust concentr ations were predicted as a function of ventilation and dust generation rates. Time-dependent airborne dust concentrations at a designated lo cation (or control volume), also were predicted from ventilation and d ust generation rates. The model calculation, solved as a 3-D lumped fo rm of control volumes, represented conservation of air mass flow rate. Swine dust used in this project had an average aerodynamic diameter o f 2 mum and 95% of the dust particles were less than 5 mum in diameter and approximately 45% of the particles were 2 mum in diameter. Both v entilation rate and dust generation rate have a significant effect on airborne dust concentration. The lumped-parameter model is shown to be capable of predicting the ventilation rate required to maintain accep table levels of airborne dust in confinement animal buildings. The acc uracy of the model is influenced by the test dust particle size unifor mity.