Spatial and temporal distribution of enthalpy in aviary heated by industrial furnace

Ferraz, Patrícia Ferreira Ponciano; Ferraz, Gabriel Araújo e Silva; Yanagi Junior, Tadayuki; Melo, Luis Fillipe Leal de; Castro, Jaqueline de Oliveira; Cecchin, Daiane

doi:10.1590/0034-737X201865040007

ABSTRACT

The enthalpy is a thermodynamic property that can be used to evaluate thermal environment for chickens, considering the meteorological variables that most influence the animal’s thermal comfort, the dry-bulb temperature and the relative humidity. The aim was to analyze and compare the spatial variability of enthalpy in a broiler aviary during three periods of the day (morning, afternoon and night) for 14 living days, using geostatistical techniques. The experiment was performed in a commercial broiler aviary located in the western mesoregion of Minas Gerais, Brazil, where 28,000 male Cobb chicks were housed. The heating system consisted of an industrial indirect-fired biomass furnace. The heated air was inflated by an AC motor, 2206 W of power, 1725 RPM. Geostatistical techniques were used through semivariogram analysis and isochore maps were generated through data interpolation by kriging. The semivariogram was fitted by the restricted maximum likelihood method. The used mathematical model was the spherical one. After fitting the semivariograms, the data were interpolated by ordinary kriging. The semivariograms along with the isochore maps allowed identifying the non-uniformity of spatial distribution of the enthalpy throughout the broiler aviary for three periods during 14 days. It was observed that in the first two days of life, during the three evaluated periods the poultry kept most of the time and in most of the poultry shed under conditions of enthalpy below the recommended level in the literature. In the12th and 13th days during the three analyzed periods were the most critical because they showed values below the comfort throughout the day, over the entire broiler aviary. Possible failures in the heating system were also observed, especially at night, which can be a discomfort source for poultry and hence generate productive and economic losses.

Keywords:
ambience; chicks; geostatistics; poultry

[1] *Corresponding Author: patricia.ponciano@deg.ufla.br

Day	Period of the day	Method	Model	C₀	C₁	C₀ + C₁	a	SDD
1	Morning	REML	Spherical	30.77	16.53	47.30	2.40	65.05
1	Afternoon	REML	Spherical	3.37	53.13	56.50	2.35	5.96
1	Night	REML	Spherical	2.24	42.02	44.27	4.35	5.07
2	Morning	REML	Spherical	0.88	11.63	12.51	2.40	7.04
2	Afternoon	REML	Spherical	0.00	30.11	30.11	4.01	0.00
2	Night	REML	Spherical	0.70	15.52	16.22	2.40	4.31
3	Morning	REML	Spherical	0.00	19.44	19.44	2.37	0.00
3	Afternoon	REML	Spherical	0.07	22.69	22.76	3.18	0.30
3	Night	REML	Spherical	4.61	20.79	25.39	4.29	18.14
4	Morning	REML	Spherical	0.00	20.97	20.97	8.06	0.00
4	Afternoon	REML	Spherical	9.58	31.13	40.72	2.21	23.54
4	Night	REML	Spherical	0.52	14.43	14.95	2.40	3.47
5	Morning	REML	Spherical	1.40	11.60	13.01	2.37	10.79
5	Afternoon	REML	Spherical	3.52	11.03	14.55	4.37	24.17
5	Night	REML	Spherical	6.23	44.69	50.92	2.27	12.23
6	Morning	REML	Spherical	0.00	14.37	14.37	6.72	0.00
6	Afternoon	REML	Spherical	0.00	15.10	15.10	7.59	0.00
6	Night	REML	Spherical	0.00	13.29	13.29	5.11	0.00
7	Morning	REML	Spherical	14.51	10.98	25.49	7.59	56.93
7	Afternoon	REML	Spherical	0.00	29.79	29.79	6.59	0.00
7	Night	REML	Spherical	1.26	17.81	19.06	6.77	6.59
8	Morning	REML	Spherical	0.00	33.04	33.04	5.46	0.00
9	Morning	REML	Spherical	8.74	14.25	22.99	9.82	38.03
9	Afternoon	REML	Spherical	6.70	13.37	20.06	3.49	33.38
9	Night	REML	Spherical	0.00	16.21	16.21	5.43	0.00
10	Morning	REML	Spherical	0.00	23.08	23.08	6.59	0.00
10	Afternoon	REML	Spherical	0.01	26.67	26.68	5.71	0.04
10	Night	REML	Spherical	0.00	32.88	32.89	5.44	0.01
11	Morning	REML	Spherical	0.00	42.54	42.54	3.49	0.00
11	Afternoon	REML	Spherical	5.50	9.67	15.17	3.41	36.23
11	Night	REML	Spherical	6.29	11.86	18.15	3.48	34.68
12	Morning	REML	Spherical	12.14	24.65	36.79	3.49	33.00
12	Afternoon	REML	Spherical	11.79	20.08	31.87	3.42	36.98
12	Night	REML	Spherical	0.09	17.19	17.28	5.97	0.52
13	Morning	REML	Spherical	0.00	39.58	39.58	5.04	0.00
13	Afternoon	REML	Spherical	5.18	7.18	12.36	3.28	41.94
13	Night	REML	Spherical	6.22	7.84	14.06	3.20	44.25
14	Morning	REML	Spherical	0.00	32.23	32.23	3.48	0.00
14	Afternoon	REML	Spherical	3.58	10.68	14.26	3.80	25.12
14	Night	REML	Spherical	2.07	10.94	13.01	3.90	15.91

Brasil

Brasil

Spatial and temporal distribution of enthalpy in aviary heated by industrial furnace

Distribuição espacial e temporal da entalpia em um aviário aquecido por fornalha industrial

ABSTRACT