This study investigates the effect of modeling the slatted floor as porous media on prediction of ammonia emissions and airflow patterns. Two approaches to determine the resistance coefficients of porous media modeling are adopted by using two geometries in CFD modeling. The results reveal that the ammonia emission with slatted floor modeled as actual size (SLM) is generally lower than the value with floor modeled as porous media (POM). Difference of air speed distribution cl.