ABSTRACT The production process of non-centrifuged cane sugar (NCS) involves a significant release of steam and heat due to the evaporation of cane juices in saucepans over a solid fuel oven. This results in a warm and moisture-saturated environment, which can be suffocating for workers. This study aimed to evaluate the bioclimatic behavior of an NCS processing facility, based on the wet bulb globe temperature (WBGT) index. In addition, solutions are suggested to mitigate possible adverse effects of heat stress. This evaluation utilized computational simulations to determine the thermal comfort perceived by the workers. The accuracy of simulations was verified against temperature and relative air humidity data collected from the facility. Bioclimatic simulations encompassed twelve treatments, involving modifications to the enclosure on the walls and lantern window, incorporating three types of roof material. The WBGT index was determined by considering the effects of the radiant heat generated by the oven and the natural ventilation area on the facility’s temperature and relative air humidity. This helps to assess the comfort experienced by the workers. The thermal zone of the oven presented heat stress conditions; therefore, rest periods and mechanical ventilation were suggested when dissipating heat and steam through natural ventilation is not possible. For workers exposed to high temperatures and thermal radiation, the use of an aluminized apron and infrared goggles for eye protection was recommended. noncentrifuged non centrifuged (NCS moisturesaturated moisture saturated environment facility (WBGT addition treatments window material facilitys s conditions therefore radiation recommended

RESUMO O processo de produção de rapadura gera alta concentração de vapor e calor devido à evaporação do caldo da cana em panelas sobre forno a combustível sólido. Isso gera um ambiente quente e saturado de umidade que pode ser sufocante para os trabalhadores. Este estudo teve como objetivo avaliar as condições ambientais de uma instalação de processamento de rapadura, com base no Índice de Bulbo Úmido e Temperatura de Globo (IBUTG) e sugerir soluções para mitigar possíveis efeitos adversos do estresse térmico. Esta avaliação utilizou simulação computacional para determinar o conforto térmico dos trabalhadores. A simulação foi validada com dados de temperatura e umidade relativa do ar da instalação. As simulações bioclimáticas foram realizadas em doze tratamentos, modificando o fechamento nas paredes e lanternim, com três tipos de materiais de cobertura. Foi determinado o Índice IBUTG, considerando os efeitos do calor radiante gerado pelo forno, e pela área de ventilação natural sobre a temperatura e umidade relativa do ar no interior da instalação, e seu efeito no conforto dos trabalhadores. A zona térmica do forno apresentou condições de estresse térmico, portanto, foram sugeridos períodos de descanso e ventilação mecânica quando não for possível a evacuação do calor e vapor através da ventilação natural. O uso de avental aluminizado e óculos infravermelhos para proteção ocular foi recomendado para os trabalhadores expostos a altas temperaturas e radiação térmica. sólido IBUTG (IBUTG tratamentos lanternim cobertura portanto

Resumen 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.

Abstract This study aimed to find the minimum area of natural ventilation suitable for coffee processing wet facilities in Colombia that have mechanical drying inside, in order to preserve the quality of coffee through a bioclimatic environment conducive to biological safety, this study was made with the help of computational simulation in EnergyPlusTM program. It was found that as the drying capacity is increased, and therefore the power of the drying machines, temperature and internal humidity tend to increase. Furthermore an inverse linear correlation was found between the area of natural ventilation and variables temperature and relative humidity. Finally, it is found relationships between the minimum area of natural ventilation and the drying capacity, in order to obtain a suitable bioclimatic environment for preserving of coffee parchment.

Este estudio tuvo como objetivo hacer una comparación bioclimática y de consumo energético entre dos instalaciones de beneficio húmedo de café en Colombia, con dos tipologías típicas de la zona cafetera colombiana, por medio de simulación computacional, evaluando específicamente el efecto del calor generado por las máquinas y el efecto del área de ventilación natural sobre la temperatura y la humedad relativa del aire en el interior de éstas construcciones y su consumo energético. El beneficiadero de café de tipología b presentó los mejores resultados en términos de temperatura y humedad relativa para conservar la calidad del grano de café y su consumo energético aproximado fue 30% del total consumido por la tipología a.

This study aimed to compare the bioclimate and energy consumption of two coffee wet processing facilities in Colombia, with two typical types of Colombian coffee, using computer simulation. Specifically, we evaluated the effect of the heat generated by machines and the effect of the natural ventilation area on temperature and relative air humidity inside these buildings and their energy consumption. The postharvest plant with typology b gave the best results in terms of temperature and relative humidity suitable to preserve the quality of the coffee bean. Its approximate energy consumption was 30% of the total consumed by typology a.

Este estudio se realizó para evaluar protocolos relativamente simples para el monitoreo de la tasa de ventilación (TV) en instalaciones pecuarias con ventilación natural (ENV). Los protocolos de ensayo se aplicaron primero a una instalación de pollos de engorde mecánicamente ventilada (EMV), donde TV se estimó con mayor precisión y luego se utilizaron para calcular la TV en la ENV. Las concentraciones de CO2 se midieron con dos esquemas de muestreo diferentes: (S1) la media de las mediciones al interior y a lo largo de la longitud de la instalación a dos alturas de 0,5 m y 1,5 m del suelo; y (S2) igual que la anterior pero con las mediciones de concentración fueron realizadas únicamente a 0,5 m del suelo. La tasa de producción de CO2 metabólico dinámico de las aves se predijo con dos algoritmos diferentes: (A1) el mantenimiento constante durante los periodos de luz y oscuridad, y (A2) que varía con la actividad de los animales sobre una base horaria. Los resultados demostraron que la combinación de S2 con A1 o A2 presentó la mejor estimación de TV en el ENV.

This study was conducted to evaluate relatively simple protocols for monitoring ventilation rate (VR) in naturally-ventilated barns (NVB). The test protocols were first applied to a mechanically-ventilated broiler barn (MVB), where VR was estimated more accurately and then were used to calculate VR in the NVB. CO2 concentrations were measured with two different sampling schemes: (S1) the average of indoor measurements along the length of the building at two heights of 0.5 m and 1.5 m from the litter floor; and (S2) same as previous but with concentration measurements taken only at 0.5 m from litter. The dynamic metabolic CO2 production rate of the birds was predicted with two different algorithms: (A1) remaining constant throughout the dark and light periods, and (A2) varying with animal activity on an hourly basis. The results demonstrated that the combination of S2 with A1 orA2 yielded the best estimate of building VR in the NVB.

Gracias a experiencias positivas en el medio urbano, las placas tipo sándwich de ferrocemento se presentan, como una alternativa a la demanda de construcciones rápidas y de bajo costo que impone la problemática de vivienda rural en América Latina. Diversas propuestas en este sentido pueden ser evaluadas previamente a través de simulaciones. Este estudio evaluó el comportamiento mecánico de tres placas tipo sándwich de ferrocemento, para definir el sistema constructivo de una propuesta de vivienda rural, a través de una simulación con elementos finitos, por medio del software SolidWorks®. Con base en un diseño previo para vivienda rural, fueron diseñadas tres alternativas de placas tipo sándwich de ferrocemento, evaluando su resistencia a la rotura y deformación, aplicando el cálculo de esfuerzos de Von Mises. Las tres alternativas mostraron resultados satisfactorios de resistencia y deformación, optando por la combinación de dos de las tres alternativas para la definición del sistema constructivo según criterios de practicidad y costos.

Thanks to positive experiences in urban, sandwich panels ferrocement type are presented as an alternative to the demand for fast, low construction cost imposed by the rural housing problem in Latin America. Various proposals in this regard may be previously evaluated through simulation. This study was performed to evaluate the mechanical behavior of three panels of ferrocement sandwich type, to define the building system of rural housing proposal, from a simulation with the application of the finite element method. Based on a preliminary design for rural housing, three alternatives were designed sandwich type ferro-plates, then evaluating their tensile strength and displacement by applying the calculation of Von Mises stress in a simulation by the finite element method, by SolidWorks® software. The three alternatives were satisfactory offset resistance and, choosing the combination of the second and third alternatives for the definition of the construction system according to criteria of practicality and costs.