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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 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.

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.

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 CO2 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.

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 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

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.

Abstract.. The objective of this study was to adapt and validate a computer model using the Computational Fluid Dinamics (CFD), in the prediction of temperature and air speed in a duct distribution system coupled to a heating furnace that is used in typical poultry houses in tropical and subtropical countries. The validation of the model with experimental data was satisfactory, presentingnormalized mean square error NMSE values of 0.25 and 0.02 for air temperature and air speed, respectively. The results evidenced that the proposed model is adequate for predicting the air speed and temperature for this type of system, and could be used to improve the efficiency of the distribution of heat inside and around air ducts using different air speeds, types of materials and dimensions. / Resumen. El objetivo de este estudio fue adaptar y validar un modelo computacional haciendo uso de la dinámica de fluidos computacional (CFD) para predecir la temperatura y la velocidad del aire en un sistema de distribución de ductos acoplado a un sitema de calefacción que es utilizado en las instalaciones avícola en los países tropicales y subtropicales. La validación del modelo con los datos experimentales fue satisfactoria, presentando valores medios normalizados del error cuadrado NMSE de 0,25 y 0,02 para la temperatura y velocidad del aire respectivamente. Los resultados muestran que el modelo propuesto es adecuado para predecir la velocidad del aire y la temperatura alrededor de este tipo de sistema, y podría ser utilizado para mejorar la eficiencia la distribución de calor en el interior y alrededor de los conductos, usando diferentes velocidades, tipos de materiales y dimensiones.

La optimización de los procesos productivos tiene granimportancia en el mundo actual debido al continuo desarrollo y avance. Con la finalidad de evaluar el desempeño productivo en el sector avícola, se hace necesaria la adecuación del ambiente interno de las instalaciones avícolas con técnicas que atiendan las exigencias de confort térmico con mayor eficiencia energética. En este trabajo, se evaluó el ambiente térmico interno de un galpón de presión negativa tipo túnel durante la primera fase de crecimiento de pollos de engorde. La evaluación de comportamiento térmico en este período fue realizada utilizando la dinámica de fluidos computacionales (CFD). El modelo computacional demostró ser una herramienta eficaz para el entendimiento y mejora de diseños bioclimáticos de ambientes internos de galpones avícolas. / The optimization of production processes hasgreat importance in the world due to the development andadvancement. In order to evaluate the productive performance in poultry production, it becomes necessary the indoor environmental adequacy of the poultry buildings by technologies that attend the requirements of thermal comfort with major energy efficiency. This study evaluated the thermal environment of a domestic shed of negative pressure tunnel type, during the first growth phase of broilers. The evaluation of the thermal behavior model during this period was made using the computational fluid dynamics (CFD). The computational model proved to be an effective tool forunderstanding and improving of bioclimatic designs of indoorenvironments to create this kind of sheds.

In tropical and subtropical countries such as Brazil, temperatures inside agricultural facilities reach values greater than those considered suitable for thermal comfort for both animals 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 simulation 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 simulation correlated well with the experimental data, and it is therefore recommended to predict the thermal behavior inside of poultry house for an animal production tunnel type.

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).

En el presente trabajo, se evaluó en la etapa de estabilización el funcionamiento de un sistema en serie, de dos biodigestores de cúpula fija GTZ y uno tipo Taiwán en clima frío, además, de encontrar los factores que determinan su funcionamiento, como lo son la producción de biogás, pH, temperaturas del afluente y del efluente, y su eficiencia en la remoción de DBO5, DQOT, SST. Se encontró una producción de biogás similar a la de biodigestores de alta tasa con una relación 3:1 entre volumen de biogás y volumen de biodigestor, remociones promedio de DBO, DQO y SST de 97,4%, 96,1 % y 95,1% respectivamente, y pH a la salida cercanos a la neutralidad, cuyos resultados son un indicativo de la alta eficiencia del sistema tanto en producción de biogás, como en remoción de carga contaminante.In the present work the operation of a system in series was evaluated in the stabilization stage of two biodigesters one of fix cupola GTZ and another type Taiwan in cold time, in addition to find the factors that determine their operation as the biogas production, pH, temperatures of the affluent and the effluent and their efficiency in the DBO5, DQOT, SST removal. There was a biogas production similar to that of biodigesters of high rate with a relation 3:1 between volume of biogas and volume of biodigester, removals average of DBO, DQO and SST of 97,4%, 96,1% and 95,1% respectively, and pH at the outlet near neutrality, whose results are a indicative of the high efficiency of the system in biogas production as in removal of pollution load.

En esta investigación se propuso determinar los valores de la relación de Poisson para la Guadua angustifolia Kunth, en la cepa y la basa del culmo, además de analizar la incidencia que ejerce la estructura interna en dicha propiedad. Los resultados indicaron que la relación de Poisson depende significativamente de la estructura del material variando entre 0,22 y 0,35 haciéndolo un producto biológico altamente heterogéneo y anisotrópico. Además, los análisis de estructura interna de tejido conductivo, parénquima y tejidos de fibras, indicaron que estos componentes varían a través de la sección transversal del culmo de la guadua.The technique of image processing was applied to determine the values of the Poisson's ratio for the Guadua angustifolia Kunth, in the “cepa” and the “basa” of the element, besides to analyze the incidence of its internal structure in this property. The results indicated that the Poisson's ratio depends upon the material structure reaching values between 0,22 and 0,35 making of this biological product a material highly heterogeneous and anisotropic. In addition the microstructure analysis of conductive tissue, parenchyma and fibers, indicated that these components vary through the cross-sectional section of the guadua element.

Se estudió la dureza del queso Edam a través de la técnica de penetrometría y análisis de perfil de textura (TPA). Los resultados estadísticos indicaron que la dureza del producto incrementó con el tiempo de maduración, pero estos valores dependen de la técnica de medición (P < 0,05). El análisis de regresión lineal mostró una relación del 85 % entre los dos métodos, donde los valores de dureza obtenidos utilizando el penetrómetro por esfera son subestimados con respecto a los valores obtenidos con la técnica del análisis de perfil de textura.Hardness of Edam cheese through penetrometry technique and texture profile analysis (TPA) was studied. The statistical results indicated that product hardness increases with ripening time but its values depends upon the measurement technique (P

Para Guadua angustifolia Kunth fueron determinados los valores últimos de los esfuerzos a tensión y cizalladura. Los resultados estadísticos mostraron valores promedios a Tensión y cizalladura de 190,70 MPa (1945,92 kgf/cm²) y 5,57 MPa (56,84 kgf/cm²), respectivamente, indicando que el material como elemento de ingeniería presenta una alta resistencia en dirección paralela a la orientación de las fibras.The ultimate shear and tension stress values were determined to the Guadua angustifolia kunth. The statistical results indicated mean values of tension and shear stress of 190,70MPa (1945,92 kgf/cm²) and 5,57 MPa (56,84 kgf/cm²), respectively, indicating that the material as engineering element has a higher mechanical resistance in the direction parallel to the fibers.

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.