Spatial variability of enthalpy in broiler house during the heating phase

Abstract

A B S T R A C TThe thermal environment inside a broiler house has a great influence on animal welfare and productivity during the production phase. Enthalpy is a thermodynamic property that has been proposed to evaluate the internal broiler house environment, for being an indicator of the amount of energy contained in a mixture of water vapor and dry air. Therefore, this study aimed to characterize the spatial variability of enthalpy in a broiler house during the heating phase using geostatistics. The experiment was conducted in the spring season, in a commercial broiler house with heating system consisting of two furnaces that heat the air indirectly, in the first 14 days of the birds' life. It was possible to characterize enthalpy variability using geostatistical techniques, which allowed observing the spatial dependence through kriging maps. The analyses of the maps allowed observing problems in the heating system in regions inside the broiler house, which may cause a thermal discomfort to the animals besides productive and economic losses.Variabilidade espacial da entalpia em galpões avícolas na fase de aquecimento R E S U M O Dentro de um galpão avícola o ambiente térmico exerce grande influência sobre o bem-estar e a produtividade dos animais, ao longo do ciclo de produção. A entalpia é uma propriedade termodinâmica que tem sido proposta para avaliação do ambiente interno de galpões de criação de frangos de corte por ser um indicador da quantidade de energia contida em uma mistura de vapor d'água e ar seco razão por que se objetivou, com o presente trabalho, caracterizar a variabilidade espacial da entalpia em um galpão de frangos durante a fase de aquecimento de pintinhos utilizando a geoestatística. O experimento foi conduzido na primavera, em um galpão comercial com sistema de aquecimento constituído de duas fornalhas de aquecimento indireto do ar, durante os primeiros 14 dias de vida das aves. Utilizando as técnicas da geoestatística foi possível caracterizar a magnitude da variabilidade espacial da entalpia permitindo a observação da dependência espacial por meio de mapas de krigagem. A análise dos mapas permitiu observar a existência de falhas no sistema de aquecimento em regiões do galpão, que podem ser possíveis causadoras de desconforto térmico para os animais, além de perdas produtivas e econômicas.

Spatial analysis of microclimatic variables in compost-bedded pack barn with evaporative tunnel cooling

“…The reach values concerning the semivariograms are relevant in determining the spatial dependence limit. They indicate the sampling limit distance in which the collected points are spatially correlated (Ferraz et al 2016). The highest values of t db range during the summer referred to the dawn period (summer), with a range of 51.035 m, and in the winter during the afternoon, with a range of 34.685 m. For RH, the highest reach values referred to the morning in the summer and during the afternoon and night in the winter, with a reach of 36.141 m, 30.240 m, and 30.240 m, respectively.…”

Thermal comfort monitoring in aviaries by a real-time data acquisition system

“…Recent experimental approaches to evaluate thermal comfort in broilers include: the use of thermal imaging (Nascimento et al, 2014) associated with the usual/typical variables, but requires high-cost measuring instruments and no records in real-time; obtaining thermal maps via real-time environment monitoring using 50 temperature sensors and 18 6. Temperature (left) and airflow speed (right), numerical (top) versus experimental (bottom); Boundary condition -Heat flux (q'' = 81.8 W m -2 ) and airflow (m = 9.7 kg s -1 ; P outlet = 30 Pa) for RH (Coelho et al, 2015); thermography for animal health (footpad dermatitis) enabling diagnosis of not visible injuries (Jacob et al, 2016); enthalpy mapping in poultry barns (Ferraz et al, 2016); use of LED -light emitting diodes to improve energy efficiency, i.e., lower electricity consumption, in aviaries (Thomson & Corscadden, 2018); CFD flow simulation for ventilation systems evaluation in poultry barns (Curi et al, 2017); development and construction of PIC microcontroller (Peripherical Interface Controller) for variables supervision and control via commercial software and hardware (Proteus ISI Professional v.8 and MATLAB v. 7.8) (Alecrim et al, 2017).…”

Assessment of spatial variability of bedding variables in compost bedded pack barns with climate control system

“…They were the nugget effect (C 0 ), sill (C 0 + C 1 ) and range of influence (a). Ferraz et al (2016Ferraz et al ( , 2020 and Ribeiro et al ( 2016) studied the spatial distribution in animal facilities and concluded that the spherical model had the best fit, because of its relatively easy ability to adjust to any cloud point. The method of Restricted Maximum Likelihood (REML) was employed to fit the data, because it allowed a less biased estimate for small data cluster (Marchant & Lark 2007).…”