Heat balance and tracer gas technique for airflow rates measurement and gaseous emissions quantification in naturally ventilated livestock buildings

Control of ammonia emissions in naturally ventilated dairy cattle facilities in Portugal

“…Recent studies have suggested that to quantify facility emission, ventilation flow rate and air gas concentrations emitted through the air outlet openings must be known [eq. (5)], and a key aspect to the emission rate determination is to calculate the air exchange rate in the facility (NGWABIE et al, 2009;SAMER et al, 2011). In this perspective, the NH 3 emission determination from facilities with forced ventilation is considered a standard procedure; however, in natural ventilation facilities the determination is more complex, since in forced ventilation the flow rate ventilation determination is simpler than the natural one (e.g.…”

“…In recent years a set of techniques for NH 3 emission measurement in livestock facilities have been developed and validated in field conditions, even for facility case where existing NH 3 concentrations are low (DORE et al, 2004;NI & HEBER, 2008;SAMER et al, 2011SAMER et al, , 2012. Recent studies have suggested that to quantify facility emission, ventilation flow rate and air gas concentrations emitted through the air outlet openings must be known [eq.…”

Balance Model to Calculate the Ventilation Rate of a Mechanically Ventilated Finishing Pig House in East China

“…hap (J· kg -1 ) is the heat of vaporization of water, that can be obtained, according to the indoor temperature Ti (°C ) from the expression: (2501-2.42 Ti)10 3 . On the other hand, A represents the relative animal activity according to the different animal actions during every 24-h period, and can be calculated as follows equations [Eons (2)]:…”

“…Quantification of gaseous emissions requires determination of the concentration of the air contaminant and the ventilation rate of the emitting source. One key issue is to estimate the ventilation rate and then to quantify the gaseous emissions [3]. In confined swine house, ventilation is critical to ensure comfortable indoor environment for animal production.…”

“…These methods largely depend on the animal production of sensible heat and latent heat. Sameer [1][2][3] investigated factors that influence moisture and heat production include flooring system, stocking, density, watering, and moisture content of the forages, animal activity and relative humidity. Sensitivity analysis showed that the estimations were more precise in cold than in warm periods, and it was concluded that heat and moisture balances were not applicable for calculations of ventilation rate in uninsulated buildings [17].…”