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Comfort index and environmental variables are indicators of thermal stress conditions inside a livestock facility. The environmental conditions of ten different constructive typologies of swine-production facilities with natural ventilation were characterized in a tropical country (Antioquia, Colombia). Temperature and humidity index (THI), enthalpy (H), animal surface temperature (ST), light intensity, and noise level were measured and computed for each typology, which were located at heights above sea levels between 8:00-23:00. Data was analyzed as a function of each typology, geographical altitude, and time of the day. It was employed descriptive statistics, analysis of variance, and contour maps to analyze the data. It was found that more than 80% of the typologies presented moderate or critical stress conditions associated with the construction typology, not suitable THI and light intensity values, especially in warm and mild-mild climates. Showing high special variability inside the facilities. New typological designs and bioclimatic conditioning for swine facilities need to be studied To be implemented in these climatic conditions.

Thermal modifications alter the physical properties and improve the natural durability of wood without using chemical impregnation processes being an environmentally friendly alternative; these improvements could be made due to changes in the internal wood structure. In this investigation, changes caused to the chemical composition and microstructure of wood Pinus oocarpa by thermal modification at 170 and 190 °C were evaluated. The thermal treatment was carried out in a prototype chamber operated during the modification steps under a steam atmosphere, with a continuous flow without pressure. The evaluation of chemical changes was performed following the TAPPI standards. Using Fourier transform infrared spectroscopy (FTIR) and optical microscopy, the wood microstructure was characterized. The results showed a decrease in holocellulose contents by 7% at 170 °C and by 9% at 190 °C; lignin contents increased at 170 °C (6%) and at 190 °C (8%) and extractives were increased by 8% (170 °C) and 13% (190 °C); the changes obtained by the spectra were related to the C-H deformation in cellulose and hemicelluloses and the complex bonds of lignin carbohydrates of the -CH3 (lignin) and CH2 (carbohydrates) groups and organic acids released during thermal modification. Thickness of tracheid walls decreased in earlywood 8% (170 °C) and 22% (190 °C) and in latewood 11% (170 °C) and 14% (190 °C); lumen diameters increased in earlywood to 170 °C (14%) and 190 °C (48%) and in latewood in 14% (170 °C) an in 20% (190 °C). At 190 °C, the cell alterations were higher. Pinus oocarpa was thermally modified at 170 °C showing better wood quality in its internal structure. RESUMEN La modificación térmica aumenta las propiedades físicas y durabilidad natural de la madera sin adición de procesos químicos de impregnación, siendo amigable con el ambiente; dichas mejoras se deben a los cambios ocasionados en la estructura interna de la madera. Por ello, la presente investigación evaluó los cambios sobre la composición química y microestructura de la madera de Pinus oocarpa por la modificación térmica a 170 °C y 190 °C realizada en un cámara prototipo que funciona durante los pasos de modificación bajo una atmósfera de vapor de agua, con un flujo continuo de corriente sin presión. La evaluación de los cambios químicos se realizó bajo las normas TAPPI. Los cambios microestructurales fueron evaluados usando Fourier transform infrared spectroscopy (FTIR) y microscopia óptica. Los resultados mostraron disminución de los contenidos de holocelulosa en 7% (170 °C) y 9% (190 °C); los contenidos de lignina aumentaron para 170 °C (6%) y a 190 °C (8%) y los extractos aumentaron un 8% (170 °C) y 13% (190 °C). Los cambios presentados en los espectros se relacionaron con la degradación C-H en celulosa y hemicelulosas y los enlaces complejos de lignina y carbohidratos de los grupos -CH3 (lignina), -CH2 (carbohidratos) y los ácidos orgánicos liberados durante la modificación térmica. El espesor de las paredes de las traqueidas disminuyó en madera temprana 8% (170 °C) y 22% (190 °C) y en la madera tardía 11% (170 °C) y 14% (190 °C); los diámetros de los lúmenes aumentaron en la madera temprana a 170 °C (14%) y a 190 °C (48%) y en la madera tardía en 14% (170 °C) y en 20% (190 °C). A una temperatura de 190 °C fueron mayores las alteraciones celulares. El tratamiento a 170 °C mostró una madera de Pinus oocarpa de mejor calidad en su estructura interna.

This study aimed to analyze the effect of the area size and location of openings for natural ventilation on the temperature and relative humidity inside a typological facility for coffee wet processing that have been using in Colombia and some South America Countries as well, with mechanical drying inside, using modeling with computational fluid dynamics modeling, in order to find the best suitable condition for preserve the quality of the coffee parchment. A significant effect was found regarding the area and location of the openings for natural ventilation on the internal hygrothermal environment, but no significant effect was found on the temperature. It was also found that the chimney effect plays a decisive role in the mass transfer of water vapor and heat to the outside of the building, and helping to maintain a suitable internal environment for the preservation of coffee.

This study aimed to evaluate the bioclimatic performance of three wet coffee processing facilities in Colombia, focused on the conditions for workers and coffee parchment, through computer simulation. In addition to temperature and relative humidity, the Wet-Bulb Globe Temperature index (WBGT) was simulated during the highest coffee production month. The proposed simulation model was able to predict hygrothermal behavior within the three coffee processing facilities. Case 3 presented the warmest environment, and case 2 the most humid environment concerning the appropriate conditions for the coffee and the worker. The WBGT index limit was exceeded in case 3. Since this type of facility emits large amounts of heat and steam, constructive modifications are suggested to improve the environmental conditions of workers and coffee. Mainly, the physical separation of the heat exchangers is recommended, which ideally should be outside the post-harvest facility. The steam produced in the drying process should be quickly evacuated with ventilation strategies. Additionally, the use of strategies that reduce the energy gain from solar radiation is suggested.

Air quality is one of the main factors that must be guaranteed in animal production. However, the measurement of pollutants is still a problem in several countries because the available methods are costly and do not always apply to the reality of the constructive typology adopted, as in countries with a hot climate, which adopt predominantly open facilities. Thus, the objective of the present study was to develop predictive models for the potential generation and emission of ammonia in the production of broiler chickens with different types of litter, different reuse cycles and under different climatic conditions. Samples of poultry litter from thirty commercial aviaries submitted to different air temperatures were analyzed. The experiment was conducted and analyzed in a completely randomized design, following a factorial scheme. Models were developed to predict the potential for generation and emission of ammonia, which can be applied in facilities with ambient conditions of air temperature between 25 and 40 °C and with wood shaving bed with up to four reuse cycles and coffee husks bed with up to six reuse cycles. The developed and validated models showed high accuracy indicating that they can be used to estimate the potential for ammonia generation and emission.

A comparison between commercial cellulose evaporative cooling pad and pads manufactured with three alternative materials was made for environmental conditions typical of tropical countries. Wind tunnel tests were carried out to compute the convective heat and mass transfer coefficients and to measure the pressure drop across each pad, obtaining expressions that can be used as reference for future simulations. Using a mathematical model, a detailed analysis of the efficiency, Temperature–Humidity Index, temperature drop and relative humidity through the pads was performed in terms of different operative and constructive conditions, such as air velocities, dry-bulb temperatures, relative humidity and pad thickness. Significant differences between the pressure drop across the pads were found, which increases with the inlet air velocity and water flow. A weak relation between the analysed variables and the inlet air velocity was found, while a high correlation between the analysed variables, pad thickness and the external environmental conditions was established. Cooling efficiencies above 40% and a Temperature–Humidity Index below the mild zone of thermal stress were obtained for the alternative panels. Although the cellulose cooling pad showed the best behaviour in all aspects, the alternative pads can be used as substituted in specific applications to reduce the Temperature–Humidity Index inside agricultural facilities.

Objetivou-se com o presente trabalho avaliar e comparar o nível de ruído emitido por um trator acoplado a uma colhedora de milho durante a operação agrícola em diferentes rotações do motor, visando identificar zonas de salubridade para os trabalhadores. O experimento foi conduzido no município de Corumbá de Goiás-GO, durante o período de colheita de milho, em julho de 2015. Os dados de nível de ruído foram coletados utilizando-se um medidor de nível de pressão sonora digital, sendo coletados em área livre de obstáculos, com dimensões de 40 x 40 m, em solo coberto com capim. O trator foi acoplado à colhedora de milho sem carga no centro desta área. O nível de ruído foi coletado tomando como base o Ponto de Referência do Assento (PRA), na altura média do ouvido do operador, e distribuindo os pontos de coleta numa malha equidistante de 5 m em relação ao PRA. Os tratamentos utilizados foram: variação da rotação do motor de 1600, 1700, 1800 e 2000 rpm. O nível de ruído encontrado neste estudo, em todas as situações avaliadas, apresentou valor médio acima de 79,0 dB(A). O uso de protetor auricular é recomendado para os operadores situados a uma distância inferior a 8,0 m em qualquer rotação do motor e 3,0 m para diferentes variações de tomadas de potências.

Confort térmico en edificaciones para procesamiento húmedo de café Resumen Este estudio tuvo como objetivo evaluar el confort térmico para trabajadores, en tres edificaciones de procesamiento húmedo de café en Colombia, utilizando el índice WBGT, y análisis de temperatura y humedad relativa a través de mapeo. Los límites recomendados del WBGT fueron excedidos en la actividad de abastecimiento de combustible de la secadora en la Edificación 3. Las tres edificaciones presentaron variabilidad higrotérmica espacial debidas a la secadora de café, y a problemas con la ventilación, volumen de control y resistencia térmica de materiales en los edificios 2 y 3. Para favorecer la transferencia de calor de la secadora al ambiente exterior, y hacer más homogéneo el ambiente térmico de las edificaciones, se recomienda instalar puentes térmicos alrededor de esta zona, y para hacer más eficiente la evacuación de vapor y calor, aumentar el área de ventilación natural en las edificaciones 2 y 3, e instalar claraboyas de ventilación sobre la secadora. Palabras clave: Arquitectura bioclimática; estrés térmico; evaluación posocupacional; índice WBGT (Wet Bulb Globe Thermometer); resistencia térmica; ventilación natural; Thermal comfort in buildings for wet processing of coffee Abstract This study aimed to assess thermal comfort for workers in three buildings for wet coffee processing in Colombia, using the WBGT index, and temperature and relative humidity analysis through mapping. The limits recommended by the WBGT index were exceeded during the activity of putting fuel in the dryer in Building 3. The three buildings presented spatial hygrothermal variability due to the coffee dryer, as well as problems with ventilation, volume control, and the thermal resistance of materials in Buildings 2 and 3. In order to favor heat transfer from the dryer to the outside environment, and to make the thermal environment of these buildings more homogeneous, it is recommended to install thermal bridges around this area, to make more efficient the evacuation of steam and heat, as well as to increase the natural ventilation area in Buildings 2 and 3, and install ventilation skylights over the dryer. Keywords: Bioclimatic architecture, thermal stress, post-occupation evaluation, WBGT (Wet Bulb Globe Thermometer) index, thermal resistance, natural ventilation Conforto térmico em instalações para processamento úmido de café Resumo Este estudo tem como objetivo avaliar o conforto térmico para trabalhadores em três instalações de processamento úmido de café na Colômbia, utilizando o índice WBGT, a análise de temperatura e a umidade relativa através de mapeamento. Os limites recomendados do WBGT foram excedidos na atividade de abastecimento de combustível da secadora na Instalação 3. As três edificações apresentaram variabilidade higrotérmica espacial devidas à secadora de café e a problemas com ventilação, volume de controle e resistência térmica de materiais nos edifícios 2 e 3. Para favorecer a transferência de calor da secadora para o ambiente exterior e tornar mais homogêneo o ambiente térmico das edificações, recomenda-se instalar pontes térmicas ao redor dessa zona e, para tornar mais eficiente a evacuação de vapor e calor, aumentar a área de ventilação natural nas edificações 2 e 3, bem como instalar claraboias de ventilação sobre a secadora. Palavras-chave: arquitetura bioclimática; estresse térmico; avaliação pós-ocupacional; índice WBGT (Wet Bulb Globe Thermometer); resistência térmica; ventilação natural. Recibido: julio 17 / 2018 Evaluado: febrero 25 / 2019 Aceptado: abril 9 / 2019 Publicado en línea: abril de 2019 Actualizado: julio de 2019

In this article, bamboo fibre bundles of "Guadua Angustifolia Kunth" specie were isolated from different locations of the basa zone: upper, middle and lower, through mechanical extraction method. The elastic modulus and the tensile strength were obtained with preliminary tensile tests. Applying the statistical analysis known as ANOVA, it was determined that the mechanical properties are similar in all the extension of the basa zone. From there, fibre bundles were extracted randomly, and a part of the fibre bundles was treated with NaOH (mercerization). Later, tensile tests with different calibration lengths were made for calculate the elastic modulus and the tensile strength of the treated and untreated fibre bundles. Best results belonged to the treated fibre bundles. A good correspondence between the results obtained in this work and the results reported in the literature was concluded.

The aim of this study was to evaluate the welfare and spatial distribution of noise levels in a swine nursery during the first three weeks of animal’s life. The climatic conditions were evaluated through the dry-bulb temperature (Tdb), relative humidity (RH) and black globe temperature and humidity index (BGHI) and allowed us to observe that the heating system influenced the conditions in the environment, and the use of the air conditioning system did not guarantee animal’s comfort conditions. The analysis on the spatial distribution of noise levels was performed using geostatistics and demonstrated the occurrence of spatial variability inside the facilities. The highest frequencies of noise levels were concentrated between 60 and 70 dB, and the highest noise values were observed near the fans. The mean BGHI values were below the thermal comfort range for piglets in all systems tested. RESUMO Objetivou-se com este trabalho avaliar o bem-estar e a distribuição espacial dos níveis de ruído no interior de uma maternidade de suínos durante as três primeiras semanas de vida dos animais. A avaliação das condições climáticas, realizada através da temperatura de bulbo seco (Tbs), umidade relativa (UR) e índice de temperatura do globo negro e umidade (ITGU), permitiu observar que o tipo de sistema de aquecimento influenciou as condições do ambiente, assim como a utilização do sistema de climatização não garantiu condições de conforto aos leitões. A análise da distribuição espacial dos níveis de ruído, realizada por meio da técnica de geoestatística, possibilitou verificar a ocorrência de variabilidade espacial no interior da instalação. As maiores frequências dos níveis de ruído concentram-se entre 60 e 70 dB. Os valores médios de ITGU situaram-se fora da faixa de conforto térmico para os leitões em todos os sistemas testados.

The present work aims to develop a mathematical model, based on fuzzy set theory, for predicting performance and the physiological responses of piglets raised in the farrowing house with different solar heating systems. To do this, a solar heater prototype was constructed using alternative materials and the heating efficiency was compared with a commercial solar heater system. In order to thermally evaluate the heaters, temperature sensors were installed in the inlet and outlet pipes of each floor and thermal reservoir. The fuzzy system was developed and the variables dry air bulb temperature (Tbs) and relative humidity (RH) of the air were defined as inputs. Based on the input variables, the fuzzy system predicts the productive performance (weight gain - WG) and physiological responses (respiratory rate - RR, rectal temperature –RT, and skin temperature - ST) of piglets raised in an environment with solar heating. Based on the results, the fuzzy model was adequate for predicting the physiological responses and productive performance of piglets, presenting low standard deviation and high correlation with the validation data. This model can be used to assist producers in decision making, especially regarding maintaining animal welfare while the thermal environment changes.

Este estudio tuvo como objetivo encontrar el área mínima de ventilación natural necesaria para instalaciones de beneficio húmedo de café con secado mecánico en su interior, con el fin de preservar la calidad de café a través de un ambiente bioclimático que propicie la inocuidad biológica, este estudio se realizó con ayuda de simulaciones computacionales en el programa EnergyPlusTM. Se encontró que a medida que se incrementa la capacidad de secado, y por ende la potencia de las máquinas de secado, la temperatura y la humedad relativa interna tienden a aumentar. Por otra parte, se encontró una correlación lineal inversa entre el área de ventilación natural y las variables temperatura y humedad relativa. Por último, se encontraron relaciones de área mínima de ventilación natural con la capacidad de secado, con el fin de obtener un ambiente bioclimático adecuado para la preservación del café pergamino.

The aim of this work was to study the vacuum drying on some quality properties of annatto seeds ( Bixaorellana . Quality properties of the dried product were analyzed using the Response Surface Methodology (RSM) considering the vacuum pressure and temperature of the drying process. In addition, the drying kinetics and stability of the dried product were studied. The analysis of the results indicated that Page’s model was the most suitable to describe the drying behavior, where the bulk density of the final product and total color change between fresh annatto seeds and dry seeds were not statistically significant. The optimum vacuum drying conditions were 45°C, 10.45 mbar and 12 h, with values of 0.358 for the water activity, 7.588 %(w.b) for the moisture content and 9.61% for the bixin content. Additionally, the bixin content presents a decreasing trend during storage for both conditions of light and darkness, where during 28 days of storage, the loss of bixin was 5.27% for light and 4.14% for darkness.

This study aimed to perform a bioclimatic comparison of wet processing facilities of coffee in Colombia, with three typical types of Colombian coffee region, through computer simulation, specifically evaluating the effect of heat and steam generated by mechanical drying machines, and natural ventilation area on the temperature and relative humidity within these facilities. The effect of the natural ventilation area was observed, to greater area of natural ventilation, lower temperature and relative humidity, i.e. it was observed that typology b behaved better bioclimatically than typology a. The indoor environment of type a (stepped type), had a greater biological risk of proliferation of fungi and bacteria, with an average temperature of 27.5 °C, and average internal relative humidity of 70.6%. In type c, as its mechanical drying machine protrudes from the building, and expel the vapor and heat produced in the drying process to the external environment, showed the best bioclimate conditions for parchment coffee, with an average temperature of 23.5 °C and average internal relative humidity of 65.5% most of the time. Este estudio tuvo como objetivo llevar a cabo una comparación bioclimática de instalaciones de beneficio húmedo en Colombia, con tres tipologías típicas de la zona cafetera colombiana, a través de simulación computacional, específicamente evaluando los efectos del calor y vapor generados por el secado mecánico, y el área de ventilación natural sobre la temperatura y la humedad relativa en estas instalaciones. Se observó el efecto del área de ventilación natural, a mayor área de ventilación natural, menor temperatura y humedad relativa, es decir, se observó que la tipología b se comportó mejor bioclimáticamente que la tipología a. El ambiente interno de la tipología a (tipología escalonada), tuvo un mayor riesgo biológico de proliferación de hongos y bacterias, con una temperatura promedio de 27,5 °C, y una humedad relativa interna promedio de 70,6%. En el tipo c, como su secadora mecánica sobresale del edificio, y expulsa el vapor y el calor producidos en el proceso de secado al ambiente externo, mostró las mejores condiciones bioclimáticas para el café pergamino, con una temperatura promedio de 23,5 °C y una humedad relativa interna promedio del 65,5% la mayor parte del tiempo.

The aim of this study was developed an energy orange juice drink with an addition to caffeine and taurine. For that, comparison of means tests were performed for four treatments, corresponding to juice added with caffeine 0.032% concentration, juice added with taurine 0.4% concentration, juice added with caffeine and taurine mixture 0.032% and 0.4%, respectively and one control, each with six replicates. The drinks were packed in low density polyethylene bags and stored at 4°C. The soluble solids (°Bx), pH, acidity, expressed as the percentage of citric acid, instrumental color and browning index and sensory characteristics (color, odor, appearance and taste) were evaluated at 0, 5, 10, 15, 20, 25 and 30 days. All the evaluated beverages presented suitable conditions for the consumption until the day 30, in addition, the added caffeine and taurine mixture treatment was which presented the best sensorial characteristics (appearance, color, odor and flavor). The acidity of all treatments increased during storage, is the largest increase for taurine treatment that was 1.37% to 2.1%, the pH decreased from 3.3 to 3.2 for all treatments except the Control; and soluble solids remained constant. In addition, the energizing agents did not affect the goldenness index of the beverages.

The objective of this work was to study the influence of different levels of thermal stress from the environment, including comfort levels (25 °C), heat stress (28 °C), moderate heat(31 °C), high heat (34 °C) and severe heat (37 °C), on the performance of broilers in the late growth (22-42 days), housed in environmental chambers. It has been determined the physiological and behavioral parameters of chickens (weight gain (WG), day weight gain (DWG), feed intake (FI), feed conversion ratio (FC), mortality (MORT), percentage of carcass of age as body weight (BW), carcass (CAR), breast (Bre), drumstick (Drum), wings (Win)), according the specific ranges of temperature; and was calculated the Temperature Index Black Globe Humidity (BGHI), for control and evaluation of the thermal environment of the treatments. In general, birds kept in temperature between 25-28 °C, during the three last week of life, performed better than those exposed to other situations, and indicating this would be the ambient temperature to the desired setting for birds in its final phase, compared with the other treatments, including those who remained at recommended temperature as thermal comfort throughout the experimental period. El objetivo de este trabajo fue estudiar la influencia de diferentes niveles de estrés térmico del ambiente, incluyendo niveles de confort (25 °C), estrés por calor (28 °C), calor moderado (31 °C), calor alto (34 °C) y calor severo (37 °C), en el desempeño de pollos de engorde en el la última fase de crecimiento (22-42 días), alojados en cámaras climáticas. Se determinaron los parámetros fisiológicos y de comportamiento de los pollos (ganancia de peso (WG), ganancia de peso diaria (DWG), consumo de alimento (FI), índice de conversión alimenticia (FC), mortalidad (MORT), porcentaje de carcasa con relación a la edad y peso corporal (BW), carcasa (CAR), pecho (Bre), muslos (Drum), alas (Win)), de acuerdo a los rangos específicos de temperatura; y se calculó el Índice de Temperatura de Globo Negro y Humedad (ITGH), para el control y evaluación térmica de los tratamientos. En general, las aves mantenidas en temperatura entre 25-28 °C, durante las tres últimas semanas de vida, se comportaron mejor que las expuestas a otras situaciones, e indicando que esta podría ser la temperatura ambiente deseada para las aves en su fase final, en comparación con los otros tratamientos, incluidos los que se mantuvieron a la temperatura recomendada como confort térmico durante todo el período experimental.

Brazil is the largest broiler meat exporter in the world. This important economic activity generates income in different branches of the production chain. However, the decomposition of residues incorporated in the poultry litter generates several gases, among them ammonia. When emitted from the litter to the air, ammonia can cause several damages to animals and man, in addition to being able to convert into a greenhouse gas. Thus, the aim of this article was to carry out a review of the ammonia emission factors in the production of broilers, the methodologies for measuring, and the inventories of emissions already carried out in several countries. The main chemical processes for generating ammonia in poultry litter have been introduced and some practices that can contribute to the reduction of ammonia emissions have been provided. The PMU, Portable Monitoring Unit, and the SMDAE, Saraz Method for Determination of Ammonia Emissions, with the required adaptations, are methodologies that can be used to quantify the ammonia emissions in hybrid facilities with a natural and artificial ventilation system. An ammonia emission inventory can contribute to the control and monitoring of pollutant emissions and is an important step towards adopting emission reductions. However, quantifying the uncertainties about ammonia emission inventories is still a challenge to be overcome.

The aim of this study was to use computational fluids dynamics (CFD) to evaluate hygiene and comfort conditions in function of temperature level and ammonia (NH3) concentration during the night in commercial poultry houses used in Brazil and countries with tropical and subtropical climates. Four models with different curtain heights and different air inlet and outlet positions were used, adopting the open building typology without thermal insulation. The validated CFD model did not present statistical differences from the experimental data, making it possible to use this model to predict the behavior in the four proposed cases. This model can be used to improve the internal conditions of the poultry facilities during the night and could be an important tool to reduce energy consumption and generate better conditions for animal production of chicks over 21 days old. RESUMO O objetivo deste trabalho foi utilizar a dinâmica de fluidos computacional (DFC) para avaliar as condições de higiene e conforto, em função dos níveis de temperatura e concentração de amônia (NH3) durante a noite, em galpões avícolas comerciais no Brasil e em países com climas tropicais e subtropicais. Para isto, foram utilizados quatro modelos com diferentes posições de altura, cortina com entrada e saída de ar adotando a tipologia de instalação aberta, sem isolamento térmico. O modelo em DFC validado não apresentou diferenças estatísticas com os dados experimentais, o que torna possível usá-lo para prever o comportamento dos quatro casos propostos. Este modelo pode ser usado para a melhoria da condição interna das instalações de aves durante a noite podendo, também, ser uma ferramenta importante para reduzir o consumo de energia e criar melhores condições para a produção de aves com idade superior a 21 dias de idade.

The main objective of this study was to experimentally validate a mechanistic model for predicting the cooling efficiency (η) of wetted porous plates built with expanded clay. The expanded clay material was physically characterized by specific mass, surface area, and volume. The model was validated with dry bulb temperature (Tdb, °C) and air relative humidity (RH, %) data, which were continuously monitored in two different points, upstream and downstream the direction of the air passing through the porous plate. Data collection was carried out consecutively for a period of 10 days, between 11:00 a.m. and 4:00 p.m. Average values for η, simulated and observed, were 74.8 ± 7.4% and 68.3 ± 8.3%, respectively. Based on the developed model, it was observed that η was higher than 40% for Tdb > 30 °C and constant RH at 45%. The simulation for predictions indicates that the increase in the air temperature greater than 20 °C may affect negatively the production in greenhouses from states located in tropical and subtropical countries as Minas Gerais, Brazil, if some design criteria in the evaporative cooling system are not revised., El objetivo principal de este estudio fue validar experimentalmente un modelo mecánistico para predecir la eficacia de enfriamiento (η) de placas porosas construidas con arcilla expandida. El material de arcilla expandida fue físicamente caracterizado encontrando su masa específica, área superficial y volumen. El modelo fue validado con datos de temperatura de bulbo seco (Tdb, ° C) y humedad relativa del aire (humedad relativa,%) que fueron continuamente monitoreados en dos puntos diferentes, en contra y a favor de la dirección del aire que pasa a través de la placa porosa. La recolección de datos se llevó a cabo de forma consecutiva durante un período de 10 días entre las 11:00 y 4:00 p.m. Los valores medios de η, simulados y observados, fueron 74,8 ± 7,4% y 68,3 ± 8,3%, respectivamente. Basado en el modelo desarrollado, se observó que η fue mayor del 40% para Tdb> 30 ° C y HR constante en 45%. La simulación indicó que el aumento de la temperatura del aire puede afectar negativamente la producción en invernaderos en Estados como Minas Gerais, Brazil, si no se revisan algunos criterios de diseño en el sistema de enfriamiento por evaporación.

The aim of this first part of the study was to estimate the greenhouse gas (GHG) emission and fixation balance in specialty coffee production in the Department of Antioquia, Colombia. The results show that an average of 1,068 kg CO 2 per kg of coffee cherry produced is fixed. The fixation and emission balance was positive of 0.271 kg CO2e / kg coffee cherry. Total GHG emission was 0,816 kg CO2e per kg coffee cherry. Emissions due to loss of carbon from soil organic matter, organic matter incorporation and coffee leaf litter decomposition, were 84.3% of total emissions and the remaining 15.7% was due to emissions from nitrogen fertilization.

Resumen El objetivo de la presente fue modelar el comportamiento térmico de un secador solar típico para café tomando en consideración algunas configuraciones geométricas en la apertura de ventanas, en pos de mejorar las condiciones de secado natural al interior de la estructura. El modelo se simuló con datos experimentales en un secador solar típico en Colombia con Ansys CFX®. Los resultados mostraron que la geometría con una apertura del 25 % en la ventana para la salida del aire aumentó la temperatura sobre la capa de café hasta 4,2 °C con respecto a la temperatura ambiente, lo cual garantiza uniformidad en el secado, mientras la geometría típica con una apertura del 100 % aumentó la temperatura hasta 3,6 °C, no obstante, con ambas aperturas se aumentó la humedad relativa sobre la capa de café hasta 0,7 % con respecto a la humedad relativa ambiental. Con la apertura máxima de las ventanas disminuyó la humedad relativa del aire. Abstract The objective of the present investigation was to computationally model a typical solar dryer for coffee, considering some alternative geometric configurations in the opening of windows to improve the thermal conditions within the drying structure which enable the water removal process of wet parchment coffee. The model was simulated in Ansys CFX® software. Simulation results showed that the geometry with an opening of 25 % in the air output window increased temperature in the coffee layer to 4.2 °C over room temperature, guaranteeing uniform drying, whereas the typical geometry with a 100 % opening increased temperature to 3.8 °C. When the maximum window opening for input and output of air was used, the relative humidity of air within the dryer decreased in comparison with the other geometries. Resumo O objetivo do presente trabalho foi modelar o comportamento térmico de um secador solar típico para café ao levar em consideração algumas configurações geométricas na abertura de janelas, a fim de melhorar as condições de secagem natural no interior da estrutura. O modelo foi simulado com dados experimentais em um secador solar típico na Colômbia com Ansys CFX®. Os resultados mostraram que a geometria com uma abertura de 25 % na janela para saída do ar aumentou a temperatura sobre a camada de café até 4,2 °C com respeito à temperatura ambiente, o que garante uniformidade na secagem, ao passo que a geometria típica com uma abertura de 100 % aumentou a temperatura até 3,6 °C, não obstante, com ambas as aberturas houve um aumento da umidade relativa sobre a camada de café de até 0,7 % em comparação com a umidade relativa ambiental. Com a abertura máxima das janelas a umidade relativa do ar diminuiu.

The thermal environment inside a rabbit house affects the physiological responses and consequently the production of the animals. Thus, models are needed to assist rabbit producers in decision-making to maintain the production environment within the zone of thermoneutrality for the animals. The aim of this paper is to develop decision trees to predict the physiological responses of rabbits based on environmental variables. The experiment was performed in a rabbit house with 26 rabbits at eight weeks of age. The experimental database is composed of 546 observed data points. Sixty decision tree models for the prediction of respiratory rate (RR, mov.min&minus, 1) and ear temperature (ET, &deg, C) of rabbits exposed to different combinations of dry bulb temperature (tdb, &deg, C) and relative humidity (RH, %) were developed. The ET model exhibited better statistical indices than the RR model. The developed decision trees can be used in practical situations to provide a rapid evaluation of rabbit welfare conditions based on environmental variables and physiological responses. This information can be obtained in real time and may help rabbit breeders in decision-making to provide satisfactory environmental conditions for rabbits.

In countries with tropical climates, such as Brazil, the high summer temperatures associated with high relative humidities are a stress factor in animal production. Excessive heat within a poultry facility causes a reduction in feed intake and production, and increased bird mortality. With the knowledge that about 75% of the radiant heat load within a facility comes from the roof, it is necessary to study alternatives that can minimize this radiation. Thus, the objective of the present work is to analyze the thermal environment inside physical broiler housing models constructed on a reduced scale (1:10), where the thermal comfort was evaluated by the black globe humidity index (BGHI) and radiant heat load (RHL). Five models built with different roofing materials were evaluated. Based on the results, it can be concluded that roofs constructed with the channel clay roofing tile (T B30), natural fiber tiles with their external side painted white (T FVP15) and tiles made of recycled long-life packaging (T LV15), provide better thermal environments within the models. En países con climas tropicales, como Brasil, las altas temperaturas asociadas con altas humedades relativas en el verano contribuyen como un factor de estrés en la producción animal. El calor excesivo dentro de una instalación avícola causa una reducción en el consumo de alimento y en la producción, y aumento en la mortalidad de las aves. Conociendo que el 75% de la carga de calor radiante dentro de una instalación viene desde el techo, es necesario estudiar alternativas que pueden minimizar esta radiación. El objetivo del presente trabajo fue analizar el ambiente térmico dentro de los modelos físicos de instalaciones de pollos de engorde construidos a escala reducida (1:10), donde el confort térmico se evaluó por el índice de humedad y de globo negro (BGHI) y la carga de calor radiante (RHL). Cinco modelos construidos fueron evaluados con diferentes materiales para techos. Basados en los resultados, se puede concluir que los techos construidos con tejas de cerámica (T B30), placas de fibra natural pintadas de blanco con en el lado externo (T FVP15) y placas de fabricadas con envases larga vida reciclado (T LV15), proporcionan los mejores ambientes térmicos.

The objective of this study was to evaluate the efficiency of the Saraz method in order to quantify ammonia emissions generated in opened or hybrid animal production facilities, and to determine an equation for the adjustment method. To do this, we developed beacon equipment, with input and output gas sectors, hoods and absorbent porous material. After the collection, the amount of ammonia captured in the environment was determined in the laboratory. Different ammonia concentrations were evaluated in addition to the different speeds of the exhaust air. Considering the results, it can be concluded that for the situations analyzed the Saraz method is efficient, but as with other methods, with an increase of air velocity and concentration, its efficiency decreases. An equation for the adjustment of the Saraz method was generated to determine the concentration and the rate of ammonia emissions inside animal facilities.

The black globe temperature (Tg) is employed in thermal comfort studies. It is mainly used to compute the Mean Radiant Temperature (MRT) required in bioclimatic analysis. A set of low cost Black Globe Thermometers (BGT) was developed to establish a suitable combination of temperature transducers, materials and globe diameters. The dynamic and static responses of the BGT were studied. A total of 18 BGT was deployed along with a data acquisition system based in the Arduino open-source platform. It was analyzed the influence of the globe material (metallic and polyethylene), globe diameter (100 mm and 67 mm for the metallic and 78 mm for polyethylene) and six types of temperature transducers (K type thermocouple, infrared temperature sensor, thermistor, RTD and two semiconductor-based transducers). It was observed that Tg estimation and response time were transducer and stimuli dependent. The BGT presents good responses for indoor measurements and it was established that the most accurate combination was achieved by the DS18B20 digital temperature sensor with a metallic globe of 67 mm of diameter.

The objective of the present work was to determinate the map the spatial distribution of noise levels inside two commercial poultry housing having different adiabatic evaporative cooling systems, during the life cycle of birds. The noise level was assessed by a digital sound level meter. The data were measured manually at each point in six predetermined sections, totaling 36 points. Spatial distribution maps of noise were generated for the inside of each animal facility, using geostatistics technique through semivariogram analysis and interpolation by ordinary kriging. It concludes that the birds were, in general, subjected to noise levels above 62.0 dBA and during clean and disinfect (decontamination period) the sheds were at approximately 35.0 dBA. The spatial profile of the noise level to the productive environment provide for the attainment of more detailed information about the studied system. Resumen El objetivo del presente trabajo fue determinar la distribución espacial de los niveles de ruido en el interior de dos instalaciones avicolas comerciales que tienen diferentes sistemas de enfriamiento evaporativo adiabatico, durante el ciclo de vida de las aves. El nivel de ruido se evaluó mediante un medidor de nivel de sonido digital. Los datos fueron medidos manualmente en cada punto en seis secciones predeterminadas, para un total de 36 puntos. Los mapas de distribución espacial de ruido fueron generados para el interior de cada instalación animal, utilizando la técnica geoestadística a través de análisis de semi variograma e interpolación por "kriging" ordinario. Se concluyó de manera general que las aves estuvieron sometidas a niveles de ruido por encima de 62,0 dBA, y durante el período de limpieza y desinfección (período de descontaminación) las instalaciones estuvieron aproximadamente a 35,0 dBA. El perfil espacial de losniveles de ruido en el entorno productivo logra proporcionar una información más detallada acerca del sistema estudiado.

The current heating system for piglets in the farrowing usually uses incandescent lamps and, in some cases, heated floors with electric resistances, which in most cases generates a high energy cost. Thus, the implantation of systems that use renewable energies in the heating of piglets can allow the thermal comfort of the animals without reducing the productive development. The objective of this research was to evaluate a computer model in Computational Fluid Dynamics (CFD), which predicts surface temperature in the heating system of a farrowing house. The study was conducted during the summer season on the swine sector of Federal University of Lavras, Brazil. For this study, a prototype solar heater using alternative materials (ASWH) was developed and compared with a conventional solar water heater (CSWH). Two floors were built of cement to test both heating systems and four thermocouple sensors (K type) with digital display were used in each system to test and evaluate the heating efficiency. Based on the results, the average surface temperature in the ASWH and the CSWH treatments was 27.9 ± 2.6 °C and 27.1 ± 1.9 °C, respectively. Therefore, the experimental data showed no significant differences from the data obtained by the model, enabling the conclusion that it is suitable for predicting the thermal conditions of this type of heating system and could be used in swine factories to predict energy consumption. Thus, this computational model can be used as a useful tool for the design and selection of heating systems used in swine maternity systems.

The aim of this study was to evaluate two types of poultry bedding litter (wood shavings and coffee husks) with increasing use cycles, the best time to proceed with composting based on the carbon/nitrogen ratio and the ability to generate ammonia. The results obtained with the present experiment conditions indicated that the litter with wood shavings in the first cycle and the litter with coffee husks in the first and second cycles presented the best behavior in terms of the C/N ratio needed for later use as compost. In regards to the contamination potential, it was found that increasing the number of reutilizations for both the wood-shaving and coffee-husk litters resulted in a greater ammonia emission.

Background: quantifying the rate of pollutant emissions, such as ammonia (NH3), from naturally ventilated animal production buildings in structures, such as those used in South America, is challenging mainly due to the challenge of determining building ventilation rate. Some methods have been developed to reduce this difficulty, but most are costly and complex, preventing their implementation.. Objective: the present work aimed to adapt and validate the Saraz method for the determination of ammonia emissions (SMDAE) from naturally ventilated poultry houses. Methods: to validate the proposed method, the ammonia emission rate (ER; NH3 mass emitted per unit time) was computed using the adjusted equation proposed by Wheeler et al.(2006; ER2). For evaluation purposes, the data obtained from the two measuring methods (SMDAE and ER2)were statistically analyzed. Results: the proposed method was considered adequate for use under conditions of natural ventilation with wind speeds greater than 0.1 m/s-1 and NH3 concentrations greater than 1 ppm. Conclusion: the method demonstrated a good correlation between its values and those obtained by the standard equation for calculating emissions based on NH3 concentration, air speed and temperature, which makes the Saraz method a reliable approach to develop ammonia inventories for naturally-ventilated poultry facilities.

En países tropicales y subtropicales como Brasil, las tempe-raturas dentro de las instalaciones agrícolas alcanzan valores superiores a los considerados como adecuadas para el con-fort térmico de los animales y las personas. Para predecir el comportamiento y la distribución de temperatura en todas las direcciones de la estructura y tomar decisiones correctas acerca del control climático en el interior de las instalaciones en tiempo real, al usar los métodos clásicos de investigación se requerirán grandes arreglos experimentales. Por lo tanto, las metodologías clásicas no ofrecen información inmediata que pueda predecir el comportamiento interno de los galpo-nes avícolas contra la variación de las condiciones ambienta-les externas e internas. El objetivo de este trabajo fue usar y validar la Dinámica de Fluidos Computacional (CFD) como herramienta de simulación para analizar la distribución de la temperatura en los galpones avícolas que trabajan con ven-tilación de presión positiva o negativa tipo túnel y con siste-mas de nebulización interna. Los resultados de la simulación numérica mostraron una buena correlación con los datos experimentales, y que la técnica numérica puede ser usada para predecir el comportamiento térmico en el interior de los galpones avícolas para instalaciones tipo túnel. In tropical and subtropical countries such as Brazil, temper-atures inside agricultural facilities reach values greater than those considered suitable for thermal comfort for both ani-mals and people. To predict the behavior and distribution of temperature in all directions of the structure and make correct decisions about the inside environment, the classic research method would require a significant experimental arrangement. Consequently, classic methodologies do not offer immediate information that might predict the internal behavior of the poultry houses against variations of external and internal conditions. The aim of this work was to use and validate the Computational Fluid Dynamics (CFD) as simula-tion tool to analyze the distribution of temperature in poultry houses with positive or negative pressure tunnel ventilation and with internal misting. The results from numerical simula-tion correlated well with the experimental data, and it is there-fore recommended to predict the thermal behavior inside of poultry house for an animal production tunnel type. Incluye referencias bibliográficas

Considerando a importância do uso de modelos reduzidos no estudo do conforto térmico na criação de aves objetivouse, com o presente trabalho, testar em um galpão comercial de frangos de corte pesadas e três modelos reduzidos construídos em diferentes escalas (1:4, 1:8 e 1:12), a validade das relações propostas e determinar, também, a escala de redução ideal para este tipo de experimento, no qual o conforto térmico foi avaliado por meio do índice de temperatura de globo negro e umidade (ITGU). Com base nos resultados pode-se concluir que, para as condições de operação e critérios de projeto estabelecidos, utilizando o ITGU como índice térmico ambiental de instalações agrícolas, é possível predizer as condições térmicas ambientais em um protótipo, a partir de modelos reduzidos em até 12 vezes. Considering the importance of the use of reduced models to the study of thermal comfort on the poultry, this work had the objective to test, in a natural scale of commercial poultry building and three reduced models constructed with different scales (1:4, 1:8 and 1:12), the validity of the relations that have been proposed. Another objective of this work was finding the ideal scale to this type of experiment where the thermal comfort was evaluated using the black globe and humidity (BGHI). Based on results it can be concluded that, for the operating conditions and established design criteria, and using the BGHI as environment thermal index of farms building, it is possible to predict the thermal environment conditions in a prototype based on reduced models up to 12 times.

En regiones de clima tropical, como es el caso de Brasil, básicamente todas las instalaciones usadas en la producción intensiva de pollos de engorde y de otros animales de interés económico que trabajan gran parte del tiempo con instalaciones abiertas y con ventilación forzada. La falta de control sobre la masa de aire renovada en cada intervalo de tiempo, bien como de la velocidad y uniformidad del aire de la ventilación que dificulta el cálculo de la cantidad de gases (amoniaco y otros) generados por la actividad en determinado momento. Este hecho constituye una dificultad en la evaluación del potencial contaminante ocurrido en estos ambientes abiertos, bien como en la comparación con los datos encontrados en los galpones cerrados utilizados en climas templados, ya que todos los países desarrollados de Europa y América del Norte disponen de metodologías para determinar el valor de las emisiones de gases en las instalaciones cerradas utilizadas en este tipo de regiones. Por lo tanto, este trabajo, busco analizar algunas metodologías usadas para determinarlas tasas de emisión de amoniaco en galpones de pollos de engorde cerrados, en países de Europa y de Estados Unidos de América (USA), y verificar la posibilidad de aplicarlas, a través de su adaptación y empleo en estructuras abiertas usadas en el Brasil y en otros países de América del Sur. Una evaluación cuantitativa, mostro quelos métodos con mayores características de adaptación a las condiciones de operación y a los diferentes tipos de acondicionamiento ambiental de galpones con sistemas de ventilación de presión positiva o con ventilación natural, son el método de trazado de sistemas de gases interno y de unidades de monitoreo continuo con las unidades portátiles de monitoriamiento (PMU) y unidades de monitoreo móviles para emisiones al aire (MAEMU). Métodos tales como el método que usa balance de masa y aquellos de difusión pasiva como el “Ferm Tube” y el método Saraz, para la determinación de emisiones de amoniaco (Saraz method for determination of ammonia emissions – SMDAE) propuesto por Osorio (2010), indican también que pueden ser adaptados para las diferentes condiciones de operación de los galpones abiertos.

The understanding of concentration and emissions distribution of gases such as ammonia (NH3) in agricultural installations is of growing importance due to its effect on health and productivity of animals and workers. The objective of this study was to use validated Computational Fluid Dynamics (CFD) model as a tool to predict NH3 concentration distribution and mass fluxes in a non-insulated broiler chicken installation with natural ventilation, typically found in subtropical and tropical countries. Results from this study indicated that simulation with CFD can be used to predict NH3 concentration distribution and mass flux inside similar installations with incident winds from different directions of entrance at the lateral opening of the installation. The most direct application of the proposed model would be to help improving the existing buildings and also to help in the conception of new ones, and may also apply the model to help in the development of NH3 emission inventories.; El entendimiento de la concentración y distribución de las emisiones de gases como el amoníaco (NH3) en instalaciones agrícolas es cada vez más importante debido a su efecto sobre la salud y la productividad de los animales y de los trabajadores. El objetivo de este estudio fue utilizar un modelo validado en Dinámica de Fluidos Computacional (CFD) como herramienta para predecir la distribución de la concentración y flujos de NH3 en una instalación de pollos de engorde sin aislamiento térmico y con ventilación natural, típicamente encontrados en países tropicales y subtropicales. Los resultados de este estudio indicaron que la simulación con CFD se puede utilizar para predecir la distribución de concentraciones y flujo de NH3 dentro de instalaciones similares con vientos incidentes con diferentes direcciones de entrada en la abertura lateral de la instalación. La aplicación más directa del modelo propuesto sería ayudar a la mejora de las instalaciones existentes y también para la concepción de nuevas, como también se puede aplicar el modelo para ayudar en el desarrollo de inventarios de emisiones de NH3.

The aim of this study was to estimate emissions of greenhouse gases (GHG) generated by the agricultural activities carried out in the Metropolitan Area of the Aburrá Valley (AMVA), located in Medellin - Colombia. A TIER 1 approach of the methodology of the Intergovernmental Panel on Climate Change, IPCC was followed. Emissions of GHG from cropland, aggregate sources and non-CO2 emissions from land were estimated and analysis of the uncertainty of activity data and emission factors were made. The estimated total emission was 63.1 and 66 Gg CO2 eq for 2009 and 2011, respectively. The greatest contribution to greenhouse gases in agricultural production was the application of nitrogen to soils in the form of synthetic and organic fertilizers, which was associated with direct and indirect N2O emissions. The main sources of uncertainty were those derived from the activity data.

The increasing size of swine farms poses an environmental risk to water bodies, considering that manure is generally applied to croplands without appropriate agronomic criteria. Objective: the present work aimed to evaluate various chemical changes occurring in soils fertirrigated with filtrated wastewater from swine facilities (FWS). Methods: 21 drainage lysimeters filled with Dystrophic Red-Yellow Latossoil were cultivated with tomato plants in protected environments, and fertirrigated with several doses of FWS, with and without fertilizer addition. Treatments were: T1: control (provided the recommended irrigation and fertilization needs for tomato plants). Treatments T2, T3, and T4, provided 100, 150, and 200% of recommended nitrogen (N), respectively, by adding filtered swine wastewater. Treatments T5, T6, and T7 provided equivalent N percentages with fertilizer addition. The experiment was conducted in a completely randomized design (seven treatments and three replications). Results: compared with initial conditions, an increase in the concentration of available phosphorus was observed, mainly in the superficial layers. The FWS addition resulted in increments in N concentration in the superficial layers, while chemical fertilizer application resulted in larger displacements in the soil profile. Conclusion: chemical fertilization was more effective than FWS for ionizing the soil solution.El aumento en el tamaño de las granjas porcinas supone un riesgo ambiental para los cuerpos de agua, teniendo en cuenta que el estiércol se aplica generalmente a las tierras de cultivo sin adecuados criterios agronómicos. Objetivo: el presente trabajo tuvo como objetivo evaluar los diversos cambios químicos que ocurren en los suelos fertirrigados con aguas residuales de instalaciones porcícolas (FWS). Métodos: 21 lisímetros de drenaje llenos con Latosuelo distrófico rojo-amarillo fueron cultivados con plantas de tomate en ambientes protegidos, y fertirrigados con varias dosis de FWS, con y sin adición de fertilizante. Los tratamientos fueron: T1: control (proveía la irrigación y fertilización recomendada para las necesidades de las plantas de tomate). Los tratamientos T2, T3 y T4 suministraron el 100, 150 y 200%, respectivamente, del nitrógeno (N) recomendado, mediante la adición de las aguas residuales filtradas. Los tratamientos T5, T6 y T7 proporcionaron los mismos porcentajes de N mediante la adición de fertilizantes. El experimento se realizó en un diseño completamente al azar (siete tratamientos y tres repeticiones). Resultados: al comparar con las condiciones iniciales, se observó un aumento en la concentración de fósforo disponible, sobre todo en las capas superficiales. La adición de FWS resultó en incrementos en la concentración de N en las capas superficiales, mientras que la aplicación de fertilizantes químicos resultó en grandes desplazamientos en el perfil del suelo. Conclusión: la fertilización química fue más eficaz que el FWS para ionizar la solución del suelo.O incremento de tamanho das granjas de suínos supõe um risco ambiental para os corpos de água, tendo em conta que as fezes dos porcos aplicam-se geralmente em terras para culturas sem ter em conta critérios agronômicos adequados. Objetivo: este trabalho teve como objetivo avaliar a alteração química que ocorre em solos adubados com irrigação de água residuária de suinocultura filtrada (FWS). Métodos: 21 lisímetros de drenagem cheios com latossolo distrófico vermelho-amarelo foram cultivados com tomateiros em ambientes protegidos e fertirrigados com varias doses de FWS, com e sem adição de adubo químico. Os tratamentos foram: T1: controle (ministrou-se a irrigação e fertilização recomendada para as necessidades do tomateiro). Os tratamentos T2, T3 e T4 ministraram 100, 150 e 200%, respectivamente, do nitrogênio (N) recomendado, por médio da adição de águas residuais filtradas. Os tratamentos T5, T6 e T7 proporcionaram as mesmas percentagens de N por médio da adição de adubos químicos. O experimento se analisou com um modelo completamente aleatorizado (sete tratamentos e três repetições). Resultados: ao comparar as condições iniciais, observou-se um aumento na concentração de fósforo disponível, principalmente nas capas superficiais. A adição de FWS resultou em incrementos da concentração de N nas capas superficiais, enquanto a aplicação de adubos químicos resultou em grandes deslocamentos no perfil do solo. Conclusão: A adubação química foi mais eficaz que o FWS para ionizar a solução do solo.

In regions with warm tropical and subtropical climates elevated air temperatures, especially during the dry seasons, can negatively affect thermal comfort inside installations used for animal and vegetative production, causing a significant decrease in production. An evaporative cooling system using non-saturated air to be introduced in the environment was employed, forcing air passage through different moist porous materials with the intention of thermal cooling, to improve the internal environment of these installations. However, difficulties in field experimentation have drastically limited the amount of information available regarding new porous materials that could possibly be used to substitute conventional material which is patented, expensive and with low durability. Therefore, the objective of the present study was to validate a computational model in Computational Fluid Dynamics (CFD) to predict cooling efficiency (h) in moist porous pads construed of expanded clay. The numerical results obtained by the proposed model showed good correlation (81%) with the experimental data, indicating its suitability to predict the behavior of these types of systems and for other porous material.En las regiones de climas tropicales y subtropicales cálidos, los altos valores de temperatura del aire, especialmente en épocas secas, pueden afectar negativamente el confort térmico dentro de los locales utilizados para la producción pecuaria y agrícola, dando lugar a una reducción significativa en su producción. Con el fin de promover la disminución de la temperatura en de las instalaciones y mejorar el ambiente interno de estas, se han utilizado los sistemas de resfriamiento evaporativo del aire que se introduce en el ambiente, abriéndose paso a través de diferentes placas porosas humedecidas. Sin embargo, dificultades en la experimentación práctica a limitado drásticamente informaciones relativas a nuevos materiales porosos posibles de ser empleados en sustitución al material convencional (Material celulósico) patentado, de elevado costo y de baja durabilidad. Debido a lo anterior, este estudio tuvo como objetivo validar un modelo computacional en dinámica de fluidos computacionales (CFD) para predecir la eficiencia del resfriamiento (h) en placas porosas de arcilla expandidas humedecidas. Los resultados numéricos obtenidos por el modelo propuesto mostraron una buena correlación con los datos experimentales (81%), lo que indica su aptitud para predecir el comportamiento de este tipo de sistemas, y de otros materiales porosos.

O presente estudo teve como objetivo avaliar as condições térmicas ambientais no interior de quatro protótipos, iguais em concepção e geometria arquitetônicas e diferentes nas soluções dos componentes de fechamento da cobertura, e avaliar o desempenho deles na produção de alface em períodos de verão. Para fins de avaliação de desempenho ambiental, foram considerados quatro tratamentos de cobertura: (T) testemunha, somente com lona plástica; (L) lona plástica e componente de ventilação (lanternim); (LS) lona plástica sob tela de sombreamento, associado a componente de ventilação (lanternim); e, (S) lona plástica sob tela de sombreamento. Como pressupostamente esperado, pode-se afirmar que as casas de vegetação sombreadas apresentaram melhor desempenho ambiental, comparativamente às não-sombreadas, e proporcionaram um ambiente mais confortável ao desenvolvimento da cultura da alface no verão.The aim of this work had concentrated in the study of solutions for the closing of the covering for greenhouses under summer conditions, experimented with the lettuce. Four covering treatments were considerate for the evaluation of the environmental performance: (T) testifier, with only plastic canvas; (C) plastic canvas and ventilation compound (an overture on the roof); (CS) plastic canvas under shading screen, with a ventilation compound(an overture on the roof) associated; and (S) plastic canvas under shading screen. It can be declared, as expected, that shaded greenhouses presented a best environment performance than the unshaded greenhouses, and provided a more comfortable environment for the growth of lettuce culture on Summer.

Actualmente, uno de los casos de mayor discusión en la producción animal, es la emisión de gases y de distribución de temperatura asociados al cambio climático y al comportamiento animal, principalmente con gases como metano (CH4) y el amoniaco (NH3). La aplicación de la dinámica de los fluidos computacionales (CFD) para predecir el comportamiento de esos gases, especialmente en el sector de producción animal, esta comenzando a ganar gran importancia. A lo largo de los años, la versatilidad, precisión y la facilidad de uso ofrecida por el CFD ha tenido una gran aceptación en la comunidad de la Ingeniería Agrícola y pecuaria en general. Por lo tanto, el CFD es regularmente utilizado para solucionar problemas ambientales asociados a control climático en instalaciones comerciales de producción animal. Debido a la mejor combinación entre la simulación computacional con CFD y modelos matemáticos, situaciones reales se han simulado con mayor confiabilidad en los últimos años. Este trabajo ofrece una revisión del estado del arte acerca de la aplicación de la técnica con CFD para determinar el comportamiento y distribución de gases al interior de instalaciones pecuarias, mostrando las ventajas y limitaciones de la técnica.Currently, one of the most discussed subjects in commercial livestock production is the emission of gases and temperature distribution, associated to climate change and animal welfare, principally with gas as methane (CH4) and ammonia (NH3). Application of computational fluid dynamics (CFD) for predicting the occurrence of these gases, especially in the animal production sector, is becoming increasingly important. Along the years, the versatility, precision and ease of use offered by CFD has caused its greater acceptance by the agricultural and animal engineering community. Therefore, CFD is regularly utilized to solve environmental problems associated to climate control in commercial animal production installations. Due to a better combination between computational simulation in CFD and mathematical modeling, realism of these simulations has become more reliable in recent years. Based on these facts, the goal of this study was to showed the recent studies using commercial Computational Fluid Dynamics (CFD) to determinate the behavior and distributions of gases inside animal production installations, showing the advantages and limitations of the technique.

El objetivo fue evaluar el uso de la arcilla expandida en concretos livianos, dosificada y elaborada de manera que fuera viable el moldeo de placas con una geometría apropiada, capaz de atender las demandas de confort térmico y de las técnicas para estructuras pecuarias. Modelos de galpones de aves fueron construidos en escala 1:12, de acuerdo con Jentzsch (2002) y localizados en dirección este-oeste. Los techos fueron construidos con tres materiales diferentes: placas prefabricadas de concreto aligerado con arcilla expandida (LWC), tejas en fibrocemento (Fcim) y tejas cerámicas (Cer). Los parámetros evaluados al interior de los modelos reducidos fueron: humedad relativa (HR), índice de temperatura de globo negro y humedad (ITGU) y carga térmica radiante (CTR), durante el verano y el invierno. Los resultados mostraron que los parámetros HR, ITGU y CTR fueron estadísticamente diferentes para cada sistema evaluado. El mejor comportamiento se presentó con el modelo de placas prefabricadas de concreto aligerado con arcillas expandidas (LWC).This research aimed to evaluate the use of the expanded clay on the light concrete, dosed and executed in order to make possible to mold the roof tiles with appropriate geometry, according to the comfort and technique demands of the animals constructions. Models of poultry livestock facilities were build in scale of 1:12, Jentzsch (2002), and were positioned on the East-West direction. The roofs were made of three different materials each one: roofing tiles of light concrete using expanded clay (LWC), roofing tiles of asbestos-cement (Fcim) and ceramic roofing tiles (Cer). The parameters evaluated inside of the reduced models were: relative humidity (RH), and black globe temperature and humidity index (BGHI) and thermal load of radiation (TLR), during the summer and winter. The results showed that the parameters RH, BGHI and TLR were statistically different among the systems. The best performance happened on the model using tiles of light concrete using expanded clay (LWC).