Diagnosis and validation by computational fluid dynamics of poultry house with negative pressure ventilation/ Diagnostico e validacao por dinamica de fluidos computacional de aviario com ventilacao a pressao negativa

• Published in: Revista brasileira de engenharia agrícola e ambiental 2019-10, Vol.23 (10), p.761
• Main Authors: de A. Cunha, Gisele C, Neto, Jose P. Lopes, Furtado, Dermeval A, Borges, Valeria P, Freire, Elias A, do Nascimento, Jose W.B
• Format: Article
• Language: Spanish
• Subjects: Fluid dynamics; Housing; Humidity; Poultry industry
• ISSN: 1415-4366
• DOI: 10.1590/1807-1929/agriambi.v23n10p761-767

Negative pressure ventilation in poultry houses has been used to enable the correction of their internal microclimates, and studies point to the heterogeneous distribution of air along the aviaries and the inadequacy of the environmental variables to the recommended ranges for thermal comfort of adult birds, especially in the hottest hours of the day. This study aimed to diagnose the facilities of a poultry house in the state of Paraiba, Brazil, regarding the distribution of environmental variables and thermal comfort; develop a computational model and validate it for Computational Fluid Dynamic--CFD simulations. Air temperature ([T.sub.air]), air relative humidity (RH) and air velocity ([V.sub.air]) data allowed characterizing the internal environment by comparison with the recommended ranges for each variable and by the temperature-humidity-velocity index (THVI). The poultry house does not provide comfort for the housed adult birds, between 12 and 14 h, with THVI indicating alert and [T.sub.air], RH and [V.sub.air] values outside the recommended ranges; the CFD model for the poultry house was validated with [T.sub.air] averages collected in the field of 27.75 [+ or -] 1.35 [degrees]C and simulated of 27.85 [+ or -] 0.55 [degrees]C, mean values of RH collected of 83 [+ or -] 12% and simulated of 78 [+ or -] 3%, and means of [V.sub.air] collected of 2.35 [+ or -] 1.35 m [s.sup.-1] and simulated of 2.50 [+ or -] 1.50 m [s.sup.-1]. Key words: thermal comfort, thermal index, simulations A ventilacao a pressao negativa em aviarios vem sendo utilizada para viabilizar a correcao de seus microclimas internos, sendo que pesquisas apontam para a distribuicao heterogenea do ar ao longo dos galpoes e inadequacao das variaveis ambientais as faixas recomendadas para o conforto termico de aves adultas, especialmente nas horas mais quentes do dia. Objetivou-se, neste estudo, diagnosticar as instalacoes de um aviario no estado da Paraiba, quanto a distribuicao das variaveis ambientais e ao conforto termico, desenvolver um modelo computacional e valida-lo mediante simulacoes utilizando dinamica de fluidos computacional--DFC. O registro da temperatura do ar ([T.sub.ar]), umidade relativa do ar (UR) e velocidade do vento ([V.sub.v]) permitiu caracterizar o ambiente interno por comparacao com as faixas recomendadas para cada variavel e por meio do indice de temperatura, umidade e velocidade do vento (ITUV). O galpao nao provem conforto as aves adultas alojadas, entre 12 e 14