scholarly journals Análise do conforto térmico em modelos reduzidos de galpões agrícola

2019 ◽  
Vol 40 ◽  
pp. 140
Author(s):  
Irajá Jantsch de Souza ◽  
Zanandra Boff de Oliveira ◽  
Ezequiel Saretta ◽  
Larrissa Ribeiro Rodrigues ◽  
Clarissa Moraes da Silva ◽  
...  

The present work had the objective of evaluating the thermal comfort by means of the Temperature and Humidity Index (ITU) inside a model of small scale poultry houses using different hedging strategies. The experiment was carried out at the Federal University of Santa Maria Cachoeira do Sul. The coverings used were: fiber cement (control), fiber cement + white paint + thermal blanket, fiber cement + white paint. The temperature and relative air humidity reading were performed inside each model and in the external area, with DTH 22 sensors controlled by Arduino, divided in four periods of summer 2017/2018. Compared to the external environment, the different coverages promoted a mean reduction of ITU from 84 to 76. Significant statistical differences between the different coverage were observed, in which the average ITU of the period of 77.31 observed in the control was reduced to 74.90 on the covers with white paint. Based on the conditions under which the study was conducted, it is recommended to cover asbestos cement + white paint to improve thermal comfort inside poultry houses.

2012 ◽  
Vol 32 (6) ◽  
pp. 1034-1040 ◽  
Author(s):  
Juliana Sarubbi ◽  
Luiz A. Rossi ◽  
Daniella J. de Moura ◽  
Rafael A. de Oliveira ◽  
Ana Paula de A Maia

In most of Brazilian pig farms, the environmental acclimatization systems run manually. For night and early morning periods, this practice isn't appropriate, because, in general, there are not employees available to run these manual systems. This research aimed to compare the bioclimatic profile of two differently constructed facilities to the external environment, considering the period from 6 p.m. to 6 a.m. during the spring, in order to show that night and early morning temperatures do not coincides with growing pig's thermoneutral zone. For this reason, acclimatization must be also carried out at these periods. It was analyzed the dry bulb temperature, relative air humidity, temperature-humidity index (THI) and enthalpy data of the sheds and external areas. Under the studied conditions, it was possible to conclude that the constructively appropriate shed appeared to be less influenced by the external environment, allowing better thermal control for growing pigs. Further research must be conducted to verify if automatic cooling systems is needed during night and early morning.


2004 ◽  
Vol 78 (1) ◽  
pp. 139-147 ◽  
Author(s):  
M. Zähner ◽  
L. Schrader ◽  
R. Hauser ◽  
M. Keck ◽  
W. Langhans ◽  
...  

AbstractThis study aimed to assess whether cows are able to cope with the range of climatic conditions they are exposed to in open stables on commercial farms in central Europe. On each of four farms, ten lactating cows were observed over a total of five weeks in winter, spring and summer. Based on continuous measurements of air temperature (–13·8 to 28·7ºC) and relative air humidity (0·26 to 0·99), a mean value of a temperature humidity index (THI) was calculated for each farm and each observation day for night and day.THI had significant effects on skin temperature and body surface temperature (infra-red thermography) both during night and day. Rectal temperature, duration of lying and cortisol concentration in the milk was significantly affected by THI during the day but not during the night. Heart rate and frequency of lying did not significantly covary with THI. Differences between farms and interactions between THI and farm were significant for most parameters. These results suggest that the climatic conditions during the day induced stronger thermoregulatory responses than the conditions during the night. Within the measured range of climatic conditions the cows were hardly exposed to severe cold or heat stress.


2011 ◽  
Vol 31 (6) ◽  
pp. 1044-1051 ◽  
Author(s):  
Patrícia C. de F Fonseca ◽  
Eduardo A. de Almeida ◽  
Roberta Passini

Among the building materials used in rural facilities, roofs are noteworthy for being largely responsible for thermal comfort, influencing the thermal balance within the shelter. This study aimed to evaluate the influence of roof on the Enthalpy (H), Thermal Load of Radiation (TLR), and Black Globe Temperature and Humidity Index (BGHI) in individual shelters for dairy calves. The design was completely randomized with three treatments: Z - zinc tile, AC - asbestos-cement tile and ACW - asbestos-cement tile painted white on the upper side. The averages were compared by the Scott Knott test at 1% probability. The results showed no statistical difference between treatments (P<0.01) and the external environment for H. For TLR, there was statistical difference among all treatments, where ACW showed the lowest TLR, 489.28 W m-2, followed by AC with 506.72 W m-2 and Z with the highest TLR, 523.55 W m-2. For BGHI, the lowest values were observed for ACW (76.8) and AC (77.4), differing significantly from Z, which obtained the highest value (81.6). The tiles with white paint on the upper side promoted the lowest TLR and the lowest BGHI, favoring the thermal environment in the shelter.


2013 ◽  
Vol 33 (1) ◽  
pp. 19-27 ◽  
Author(s):  
Eduardo A. de Almeida ◽  
Roberta Passini

The research was developed to evaluate the use of different types of roofing materials regularly used in poultry houses. Measurements of thermal comfort were made through the use of techniques such as the Black Globe and Humidity Index (BGHI), the Thermal Heat Load (THL) and Enthalpy (H). Conducted in the State University of Goiás, during the months of April and May, 2011, the experiment was composed of five different treatments: AC - Asbestos cement tiles, BA -Bamboo tiles, BAP - Bamboo tiles painted in white, FB -Vegetable fiber tiles and bitumen, FBP -Vegetable fiber tiles and bitumen painted in white. The experiment consisted in 15 repetitions, which were considered the different days of measurements taken. Throughout the studied period, the time of the day considered the least comfortable was the one observed at 2:00pm, and the coverage of vegetable fiber and bitumen showed the highest value of BGHI (84.1) when compared to other types of coverage, characterizing a situation of lower thermal comfort, and no difference was found for THL and H on treatments in the studied region.


2013 ◽  
Vol 56 (1) ◽  
pp. 509-517 ◽  
Author(s):  
D. Němečková ◽  
I. Knížková ◽  
P. Kunc ◽  
L. Stádník

Abstract. The objective of this study was to compare microclimatic conditions in three different housing systems designed for calf rearing – individual wooden hutches, individual tarpaulin hutches and individual pens under shelter – and to evaluate the thermal comfort of calves reared in these systems. Air temperature, relative air humidity and the rectal temperature of calves (n=324) were measured in the hutches and pens during three consecutive years. The hypothesis that the climatic conditions of different housing system designs used in calf rearing affect the thermal comfort of calves was confirmed, as the design of the individual housing systems affected microclimatic conditions and subsequently the rectal temperature of the housed calves as well. Statistically significant differences (P<0.05) were found between the shelter and individual outdoor calf hutches in relation to the measured parameters. In the summer, the shelter showed a significantly (P<0.05) lower air temperature and significantly higher level of both relative air humidity and calf rectal temperature. These significantly higher rectal temperatures in both summer and in transitional periods (from March to June and from September to December) can be explained by microclimatic conditions and specifically by the combination of air temperature and the highest relative humidity that caused less comfortable microclimatic conditions for calves. The high relative humidity is probably caused by inadequate ventilation under the shelter. Therefore, new technology of calf housing under shelter could be recommended as suitable housing only if adequate ventilation is provided.


2019 ◽  
Vol 34 (3) ◽  
pp. 377-388
Author(s):  
Zanandra Boff Oliveira ◽  
Alberto Eduardo Knies

ANÁLISE BIOCLIMÁTICA E INVESTIGAÇÃO DO CONFORTO TÉRMICO EM AMBIENTE EXTERNO NA REGIÃO CENTRAL DO RS   ZANANDRA BOFF DE OLIVEIRA1, ALBERTO EDUARDO KNIES2   Professora adjunta, Coordenadoria Acadêmica, Universidade Federal de Santa Maria Campus em Cachoeira do Sul, Rua Ernesto Barros, nº 1345, Bairro Santo Antônio, cep: 96506-322, Cachoeira do Sul – RS, Brasil. E-mail: [email protected] Professor adjunto, Universidade Estadual do Rio Grande do Sul Unidade em Cachoeira do Sul, Rua Sete de Setembro, nº 1040, Bairro Santo Centro, cep: 96508-010, Cachoeira do Sul – RS, Brasil. E-mail: [email protected]   RESUMO: o presente trabalho teve como objetivo realizar a análise bioclimática e a investigação do conforto térmico em ambiente externo na região central do RS. Para isso, utilizaram-se os seguintes índices de conforto térmico: índice de temperatura e umidade (ITU) e índice de desconforto humano (IDH). Os dados meteorológicos de temperatura do ar máxima (Tmax) e mínima (Tmin) e umidade relativa do ar máxima (URmax) e mínima (URmin) foram obtidos de uma série de 10 anos (2005-2015) de dados de uma estação meteorológica automática instalada em Santa Maria (RS). A temperatura do ponto de orvalho foi estimada a partir da Tmax e Tmin e da URmin e URmax, respectivamente. Os índices de conforto térmico foram calculados a partir das médias diárias do período (10 anos) para a situação de máximo desconforto térmico que ocorre nos extremos: 1) quando a temperatura do ar é máxima e a umidade relativa do ar é mínima - denominados de ITUmax e IDHmax; 2) quando a temperatura do ar é mínima e a umidade relativa do ar é máxima - denominados de ITUmin e IDHmin. Em função da elevada amplitude térmica mensal (>10ºC<18ºC) e diária (>5ºC<10ºC), os valores dos índices de conforto térmico (ITU e IDH) variam entre 51,5 e 80,4, indicando que a situação de conforto térmico do ambiente externo na região central do RS vai nos extremos de estresse térmico devido ao frio (julho) a estresse térmico devido ao calor (janeiro). No período de maio a outubro o conforto térmico ocorre na Tmax, mas na Tmin a situação é de desconforto a estresse por frio. No período de novembro a fevereiro, o conforto térmico ocorre na Tmin, mas na Tmax ocorre desconforto a estresse térmico por calor. Nos meses de março e abril, o desconforto ocorre tanto por frio quanto por calor. Dessa forma, para a produção zootécnica e para o conforto térmico humano na região central do RS, são necessárias práticas de acondicionamento ambiental que visem a minimização do estresse térmico.   Palavra-chaves: índices de conforto térmico; análise bioclimática; amplitude térmica.   BIOCLIMATIC ANALYSIS AND RESEARCH OF THERMAL COMFORT IN EXTERNAL ENVIRONMENT IN THE CENTRAL REGION OF RS   ABSTRACT: The present work had the aim of performing the bioclimatic analysis and the investigation of the thermal comfort in an external environment in the Central region of RS. For this, the following thermal comfort indexes were used: temperature and humidity index (THI) and human discomfort index (HDI). The maximum air temperature (Tmax) and minimum air temperature (Tmin) and maximum relative humidity (URmax) and minimum air humidity (URmin) were obtained from a series of 10 years (2005 to 2015) of data of an automatic meteorological station installed in Santa Maria - RS. The temperature of the dew point was estimated from the Tmax and Tmin and the URmin and URmax, respectively. The thermal comfort indexes were calculated from the daily average of the period (10 years) for the situation of maximum thermal discomfort that occurs in the extremes: (i) when the air temperature is maximum and the relative humidity of the air is minimal - denominated of THImax and HDImax; (ii) when the air temperature is minimal and the relative humidity of the air is maximum - denominated THImin and HDImin. In function to the high temperature amplitude, monthly (> 10ºC <18ºC) and daily (> 5ºC <10ºC), the values of thermal comfort indexes (THI and HDI) vary from 51.5 to 80.4, indicating that thermal comfort of the external environment in the Central region of RS goes in the extremes of thermal stress due to the cold (July) to the heat stress due to the heat (January). In the period from May to October the thermal comfort occurs in Tmax, but in Tmin the situation is of cold stress discomfort. In the period from November to February, thermal comfort occurs in Tmin, but in Tmax, heat stress discomfort occurs. In the months of March and April the discomfort occurs as much by cold as by heat. Thus, for a zootechnical production and human thermal comfort in the central region of RS, it is necessary to practice environmental conditioning to minimize thermal stress.   Keywords: thermal comfort index; bioclimatic analysis; thermal amplitude.  


2020 ◽  
Vol 328 ◽  
pp. 01001
Author(s):  
Natalia Krawczyk ◽  
Andrej Kapjor ◽  
Łukasz J. Orman

This study presents the issue of thermal comfort based on the Fanger model. The research was conducted in 5 rooms in the autumn-winter period. The research consisted of measurement of thermal environment parameters, air temperature and flow rate, relative air humidity, globe temperature sensor and light intensity. During the research, the students filled in questionnaires concerning thermal sensation. This allowed them to express their assessment of thermal comfort (predicted mean vote PMV and predicted percentage of dissatisfied PPD), as well as their preferences concerning the prevailing room conditions. Differences between the actual average predicted rating index and the Fanger model were shown. It can be noted that Fanger’s model does not reflect the results of the respondents.


2019 ◽  
Vol 70 (4) ◽  
pp. 1187-1191
Author(s):  
Carmen Otilia Rusanescu ◽  
Marin Rusanescu ◽  
Cosmin Jinescu ◽  
Gigel Paraschi

The purpose of this paper is to estimate the conditions of human comfort in Bucharest. To describe the influence of the climate on human health, several indices have been developed describing the degree of physiological comfort offered by the meteorological conditions, taking into account meteorological parameters registered daily by the weather station at the Polytechnic University of Bucharest, Faculty of Biotechnical Systems Engineering: temperature and relative air humidity, wind speed. The following indices were analyzed: summer SCHARLAU index (ISE), winter SCHARLAU index (ISH), thermohigrometric index (THI), wind cooling power (skin stress index) (P), temperature equivalent to cooling wind power Tpr, to determine the influence of thermal comfort on health.


2020 ◽  
Vol 21 (2) ◽  
pp. 200-205
Author(s):  
Jonathan Willian Zangeski Novais ◽  
Sílvia Finger Dalmaso ◽  
Roberta Daniela de Souza ◽  
Naara Soares dos Santos Brito

O crescimento mal planejado das grandes cidades acarreta o aparecimento das chamadas ilhas de calor urbano, que consequentemente geram desconforto nos cidadãos. Em um contexto universitário, o desconforto térmico pode prejudicar a concentração e desempenho de alunos, professores e funcionários. Assim simulou-se o microclima da Universidade de Cuiabá, campus Barão, com o objetivo de analisar as partes críticas desconfortáveis do campus e sugerir estratégias que possam melhorar o conforto térmico local. Para a simulação utilizou-se o software ENVI-met, que espacializa as variáveis temperatura do ar e umidade relativa do ar, sendo simulados os horários de 08, 14 e 20 horas no período chuvoso e seco, conforme a sazonalidade climática local. Encontrou-se como zonas críticas a entrada do Campus, Bloco A, a área de convivência nos intervalos dos alunos e o estacionamento, atingindo temperaturas máximas de 34 ºC. Outra questão que causa preocupação é a baixa umidade relativa do ar no período seco, em que as 14 horas chegou a mínima 23%. Conclui-se que a intensificação de áreas verdes no campus, como gramados e arborização, a substituição de pavimentos, substituindo parte da área asfáltica por pavimentos de calor específico menor, e a utilização de telhado verde, podem contribuir para a melhoria do conforto térmico do campus.   Palavras-chave: Conforto Térmico. Temperatura do Ar. Umidade Relativa do Ar. Telhado Verde. Arborização.   Abstract The poorly planned growth of large cities leads to the appearance of the so-called urban heat islands, which consequently generate discomfort for citizens. In a university context, thermal discomfort can impair the concentration and performance of students, teachers and staff. Thus, the microclimate of University of Cuiabá, Barão campus was simulated, with the objective of analyzing the uncomfortable critical parts of the campus and suggesting strategies that can improve the local thermal comfort. For the simulation, the ENVI-met software was used, which spatializes the variables air temperature and relative air humidity, simulating the times of 08, 14 and 20 hours in the rainy and dry period, according to the local climatic seasonality. Critical areas were the entrance to Campus, Block A, the living area in the students’ break time and the parking, reaching maximum temperatures of 34ºC. Another issue that causes concern is the low relative air humidity in the dry period, when the 14 hours reached a minimum 23%. It is concluded that the green areas intensification at the campus, such as lawns and afforestation, the replacement of pavements, replacing part of the asphalt area with pavements with lower specific heat, and the use of a green roof, can contribute to the improvement of the campus thermal comfort.   Keywords: Thermal Comfort. Air Temperature. Green Roof. Afforestation.  


2000 ◽  
Vol 25 (4) ◽  
pp. 329-330
Author(s):  
R.J.B. Hemler ◽  
G.H. Wieneke ◽  
P.H. Dejonckere

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