Tag Archives: air velocity

xxx M.O. Vilela, R.S. Gates, M.A. Martins, M. Barbari, L. Conti, G. Rossi, S. Zolnier, C.G.S. Teles Junior, H.H.R. Zanetoni, R.R. Andrade and I.F.F. Tinôco
Computational fluids dynamics (CFD) in the spatial distribution of air velocity in prototype designed for animal experimentation in controlled environments
Abstract |
Full text PDF (774 kB)

Computational fluids dynamics (CFD) in the spatial distribution of air velocity in prototype designed for animal experimentation in controlled environments

M.O. Vilela¹*, R.S. Gates², M.A. Martins¹, M. Barbari³*, L. Conti³, G. Rossi³, S. Zolnier¹, C.G.S. Teles Junior¹, H.H.R. Zanetoni¹, R.R. Andrade¹ and I.F.F. Tinôco¹

¹Federal University of Viçosa, Department of Agricultural Engineering, Av. Peter Henry Rolfs, s/n Campus University of Viçosa CEP: 36570-900, Viçosa, Minas Gerais, Brazil
²University of Illinois at Urbana-Champaign, Department of Agricultural and Biological Engineering, 1304 West Pennsylvania Avenue 61801, Urbana, USA
³University of Florence, Department of Agriculture, Food, Environment and Forestry, Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: monique.vilela@ufv.br; matteo.barbari@unifi.it

Abstract:

Maintaining a comfortable and productive thermal environment is one of the major challenges of poultry farming in tropical and hot climates. The thermal environment encompasses a number of factors that interact with each other and reflect the actual thermal sensation of the animals. These factors characterize the microclimate inside the facilities and influence the behaviour, performance and well-being of the birds. Thus, the objective of this study is to propose and validate a computational model of fluid dynamics to evaluate the spatial distribution of air velocity and the performance of a system designed to control air velocity variation for use in experiments with birds in controlled environment. The performance of the experimental ventilation prototype was evaluated based on air velocity distribution profiles in cages. Each prototype consisted of two fans coupled to a PVC pipe 25 cm in diameter, one at each end of the pipe, with airflow directed along the entire feeder installed in front of the cages. The contour conditions considered for the simulation of airflow inside the cage were air temperature of 35 °C at the entrance and exit of the cage; air velocity equal to 2.3 m s-1 at the entrance of the cage; pressure of 0 Pa. The model proposed in this study was representative when compared to the experimental measurements, and it can be used in the study of air flow behaviour and distribution for the improvement of the prototype design for later studies.

Key words:

, , ,




67-78 O. Sada and B. Reppo
Indoor climate of pigsty with deep litter and liquid manure system in summer
Abstract |
Full text PDF (278 kB)

Indoor climate of pigsty with deep litter and liquid manure system in summer

O. Sada and B. Reppo

Institute of Technology, Estonian University of Life Sciences,Kreutzwaldi St. 56, 51014 Tartu, Estonia; e-mail: boris.reppo@emu.ee

Abstract:

Construction of big deep-litter pigsties and pigsties without litter (using liquid manure systems) is becoming more extensive. Due to lack of knowledge concerning animal-keeping in big pigsties, it has become necessary to study the work environment in pigsties and, in particular, their indoor climate. In order to determine the impact of the outdoor climate, different methods for animal-keeping and tending activities on indoor climate during summertime, the air temperature, relative humidity, air velocity and contents of oxygen, carbon dioxide and ammonia were measured on a daily basis at the height of 1.5 m from the floor above the pigsty in the centre of deep-litter (800 fattening pigs) and liquid manure system (600 young pigs) pigsties. Simultaneously outdoor air temperature and relative humidity were measured. Data Logger equipment with relevant sensors and Gas Monitor Pac III were used for studying the indoor climate. Hydrolog equipment was used for measuring the parameters of outdoor climate. Measurement results were processed by using computer programmes AMR Win Control, HW3 and MS Excel.It turned out that during summertime the indoor climate of pigsties was most affected byoutdoor climate and tending works. The daily average indoor temperature (17.04 and 17.60°C respectively; outdoor temperature, 18.15 and 8.75°C) and relative humidity (68.11 and 78.59% respectively; outdoor relative humidity, 71.88 and 84.19%) remained within recommended limits for animals in the deep-litter pigsty and in the pigsty without litter. However, partial floor heating had to be used in the morning in order to ensure optimum indoor temperature and relative humidity in the pigsty for young pigs. Due to good ventilation in the pigsties the daily average contents of carbon dioxide (0.06 and 0.07%) and ammonia (20.9 and 8.7 ppm) remained within standard limits. Ammonia content in pigsties was higher during tending works, reaching 43 and 27 ppm. As a result of the study, the graphical and empirical relationship was determined between ammonia concentration and indoor air both in terms of air temperature and combined effect of temperature and relative humidity.

Key words:

, , , , , , , , ,




45–54 O. Sada and B. Reppo
Impact of tending work on pigsty inner climate in winter
Abstract |
Full text PDF (187 kB)

Impact of tending work on pigsty inner climate in winter

O. Sada and B. Reppo

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi St. 64, 51014 Tartu, Estonia; e-mail: boris.reppo@emu.ee

Abstract:

Inner climate at pigsty is in strong correlation with outdoor climate and tending work. Up to now, main research has been conducted to investigate air temperature and relative humidity, in order to be able to offer solutions to pigsty ventilation. At the same time, little data can be found about pigsty air gas content depending on pigs’ function work. With the aim of investigating the impact of outdoor climate and tending work on the inner climate at a pigsty of fatlings and youngs, the research was conducted to measure the air temperature, relative humidity and the content of oxygen, carbon dioxide and ammonia at these pigsties in winter time diurnally at the height of 1.5 meters. To measure the inner climate, Data Logger, appropriate sensors and the computer program PC AMR Win Control were used. At the same time, the winter outdoor air temperature and relative humidity were measured using Rotronic logger. The results of the research presented in the article concern the air temperature and velocity, relative humidity and the content of oxygen, carbon dioxide and ammonia of the working environment, measured in different places and heights of the room during daytime and diurnally above the pigpen. It became evident that the pigsty’s inner air temperature was within the extent recommended, but the air relative humidity increased partly very high. The carbon dioxide content partly exceeded the established limits. The average measured ammonia also exceeded the limits in some cases but always increased during the tending work.

Key words:

, , , , , , , , , , , ,