Measurement and numerical simulation of single-sided mechanical ventilation in broiler houses

In recent years, some broiler production farms especially in Mediterranean areas, have incorporated single-sided mechanical ventilation (i.e. air inlets and fans are located in the same lateral wall). However, little scientific information on the performance of mechanical single-sided ventilation systems is available to date. This ventilation method is fitted to broiler houses because this ventilation system appears appropriate to diminish the stress and mortality of broilers during hot seasons in this climate. To analyse the single-sided ventilation method scientifically, the indoor environments of broiler houses were examined by numerical simulation using computational fluid dynamics (CFD) with validation using a range of different buildings with direct measurements using a multi-sensor system. An analysis of variation of the results of the validation tests produced to a p-value of 0.3908. Thus, the methodology employed (i.e. CFD or sensors) was not significant. The CFD simulations showed a wide range of values for air velocity: the minimum value of air velocity at broiler level was 0.52 ± 0.40 m s−1 and the maximum was 1.29 ± 0.41 m s−1. Two major conclusions were drawn in terms indoor air velocity: (i) excessive heterogeneity in the plane where the animals were located; and (ii) insufficient air movement to contribute to the thermoregulation of the birds and lower their internal heat and associated thermal stress in occasional periods of hot weather.