Tag Archives: thermal comfort

687–693 L.C.S.R. Freitas, I.F.F. Tinôco, F.C. Baêta, M. Barbari, L. Conti, C.G.S. Teles Júnior, M.G.L. Cândido, C.V. Morais and F.C. Sousa
Correlation between egg quality parameters, housing thermal conditions and age of laying hens
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Correlation between egg quality parameters, housing thermal conditions and age of laying hens

L.C.S.R. Freitas¹, I.F.F. Tinôco¹, F.C. Baêta¹, M. Barbari²*, L. Conti², C.G.S. Teles Júnior¹, M.G.L. Cândido¹, C.V. Morais¹ and F.C. Sousa¹

¹ Federal University of Viçosa, Department of Agricultural Engineering, Avenue Peter Henry Rolfs, University Campus, BR36570-900, Viçosa-MG, Brazil
² University of Firenze, Department of Agricultural, Food and Forestry Systems, Via San Bonaventura, 13, IT50145 Firenze, Italy
*Correspondence: matteo.barbari@unifi.it; leticia.ramos@ufv.br

Abstract:

High environmental temperatures cause a decrease in feed consumption by laying hens and, as a consequence, a reduction of productive performance and egg weight. The hens age is a factor influencing the albumen quality that tends to be more liquefied in older hens. Such variable is analysed by the determination of the Haugh Unit.
The correlations between the egg quality variables (egg weight and Haugh Unit), the  thermohygrometric conditions in the facility and the age of laying hens were determined in the study and evaluated based on the Pearson correlation coefficient (r) and their significance at the 5% level. The microclimatic data and the eggs were collected in 20 points of poultry facility with birds of 43, 56, 69, 79 and 86 weeks of age, totalling 100 samples.
The results show significant correlations between egg weight and temperature (r = -0.238), egg weight and hens age (r = 0.310), Haugh Unit index and hens age (r = -0.256); a non-significant correlation between the quality parameters with the relative humidity of the air inside the barn. The egg weight had a weak negative correlation with the ambient temperature and a weak positive correlation with the hens age. Concerning the Haugh Unit, a weak negative correlation with the age of the animals was found. The weak or non-existent correlation of temperature with egg quality parameters can be due to the environmental conditions that remained in the range of thermal comfort for the animals during the trials.

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237-244 M. Zajicek, and P. Kic
Heating of large agricultural and industrial buildings
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Heating of large agricultural and industrial buildings

M. Zajicek¹,* and P. Kic²

¹Institute of Information Theory and Automation, The Academy of Science of The Czech Republic, v.v.i.; *Correspondence: zajicek@utia.cas.cz 2Czech University of Life Sciences Prague, Faculty of Engineering, Czech Republic

Abstract:

This paper presents the results of the simulation calculations used in the selection and design of an appropriate method of heating of large buildings for agricultural or industrial purposes. These halls are characterized by a large built-up area, large room height and high consumption of energy for heating. The aim of the simulation calculation was to find a way of heating, which leads to a reduction in energy consumption while maintaining the required thermal comfort of indoor environment. The calculations were performed using the CFD software ANSYS-Fluent. For comparison of variants, a 3D model was used, including a heat source, natural convection and heat transfer through surrounding structures. The results of the thermal comfort of the working environment in the level of people or the growing zone of plants or the storage space for goods were mainly studied. The second area of interior space, especially important in terms of heat losses, is the level of the ceiling. The results of the calculations provide a detailed analysis of the vertical temperature profiles and the effect of the surrounding walls surface temperature on the thermal state of an indoor environment. The created model was verified according to the results of experiments in large buildings equipped with different heating systems. Based on the results of the simulation calculations and according to the results of experimental measurements, radiant heating method seems to be the suitable heating system solution for studied types of buildings.

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