Calculation of the ammonia emission reduction potential in a naturally ventilated cattle stable using a numerical model

Cattle farming in naturally ventilated stables is a major source of ammonia emissions. Numerical models of livestock buildings make it possible to virtually simulate the flow, the concentration distribution of harmful gases and the emission behaviour of a real barn under any relevant operating condition on the computer. Thus, ventilation strategies for naturally ventilated dairy cattle stable can be developed, which reduce emissions and increase animal welfare at the same time. In the present work the numerical model of a real existing dairy cattle barn was extended by a partial underfloor suction with subsequent exhaust air treatment and the emission behaviour at different inflow conditions and operating states was calculated. The simulations showed a clear potential for a reduction of ammonia emissions and possibilities for optimizing the ventilation of an open barn system. In comparable studies, numerical simulations have also shown a positive effect of partial underfloor suction with regard to ammonia emissions in naturally ventilated cattle barns. In this context, a fundamentally improved ventilation of cattle barns by partial underfloor suction was also found.