RESUMO O conforto térmico no interior de instalações de criação de frangos de corte é essencial na obtenção de bons resultados nesta atividade de produção. A avaliação das condições termodinâmicas adequadas requer a medição e controle, geralmente implicando em custos e manutenção especializada. Neste trabalho, objetivou-se monitorar a distribuição de temperatura, umidade relativa e velocidade do ar utilizando sistema desenvolvido, de baixo custo, de código aberto e de fácil uso, com Arduíno (hardware) e Scilab (software) para aquisição de dados em tempo real. Os sensores foram instalados em uma unidade de produção existente (Cianorte, PR), com medições para o ambiente interno (20 sensores de temperatura/umidade e 2 sensores de pressão diferencial, respectivamente, a 0,5 e 1,5 m de altura) e para ambiente externo (pressão e velocidade do vento, a 1,5 m de altura). Sistema de aquisição de dados permitiu a comunicação com sensores, que são facilmente lidos por computador e armazenados em um arquivo de dados. O sistema de aquisição de dados desenvolvido provou-se eficiente quando aplicado em uma instalação de criação comercial de frangos de corte, permitindo o monitoramento em tempo real para os parâmetros de conforto térmico.

ABSTRACT Thermal comfort inside broiler husbandry facilities is essential in obtaining good results in the production activity. Assessment of adequate thermodynamic conditions requires measurement and control, usually implying costs and specialized maintenance. The objective of this research was to monitor the temperature, relative humidity and air speed distributions by a developed low-cost, open-source and easy-to-use measurement system, using Arduino (hardware) and Scilab (software) for real-time data acquisition. Sensors were installed in a real facility (Cianorte, PR), with measurements for internal ambient (20 sensors for temperature/relative humidity, and two sensors for differential pressure, respectively 0.5 and 1.5 m high) and external ambient (pressure and wind speed, 1.5 m high). Data acquisition system has enabled communication with sensors which are easily read by the computer and stored in a data file. The developed data acquisition system proved to be efficient when applied in a commercial broiler husbandry facility, enabling real-time monitoring for thermal comfort parameters.

RESUMO A avaliação do consumo de combustível em motores de combustão interna (MCI) em máquinas e equipamentos agrícolas é importante na determinação do desempenho em condições diversas de operação sobretudo quando biocombustíveis são utilizados. Este trabalho consiste da avaliação experimental do consumo de gasolina/etanol de um MCI, ciclo Otto, 2T e um cilindro, acionando um soprador de ar, utilizado em aplicações na agropecuária e afins. Foi considerada metodologia para realização de ensaios em MCI não automotivos, baseada em normas técnicas NBR/ABNT. Os resultados apresentados se referem ao funcionamento com misturas combustíveis comerciais e não-comerciais. Curvas características para o equipamento ensaiado são apresentadas identificando as condições de consumo e o comportamento em toda a faixa operacional de rotações (RPM), para cinco misturas combustíveis (gasolina/etanol). Nas condições operacionais de rotações mínimas e máximas as misturas de 20 e 30% de etanol na gasolina apresentaram o maior e o menor consumo, respectivamente.

ABSTRACT Evaluation of fuel consumption in internal combustion engines (ICE) of agricultural machinery and equipment is important in determining the performance under various operating conditions, especially when using biofuels. This study consisted of experimental evaluation of the gasoline (petrol)/ethanol consumption in a two-stroke 1-cylinder ICE, Otto cycle, functioning as an air blower for agriculture and related applications. A methodology for tests of non-automotive ICE, based on ABNT/NBR technical standards, was considered. The presented results refer to operation with commercial and non-commercial fuel blends. Characteristic curves for the tested equipment are presented, identifying consumption conditions and trend in the whole operating range of angular speeds (RPM), for five fuel blends (gasoline/ethanol). For the operating conditions of minimum and maximum angular speeds, 20 and 30% ethanol blends had the highest and lowest fuel consumptions, respectively.

ABSTRACT This research presents results of the assessment of solid biofuels (residual biomasses from agricultural crops) in the state of Mato Grosso do Sul, in the period 2007-2012, for energy in agricultural uses. It is pointed out the available quantity, its geographic location at micro and meso regions and energy conversion potential. The methodology is based on a survey on municipal agricultural production of the Brazilian Institute for Geography and Statistics (quantity and local availability, per year) followed by determination of the amounts of agricultural assessed residues, and then applying equations from the literature to estimate the amount of energy (J) and power (kW) obtained from the thermal conversion of residual biomasses. Results are presented for three residual biomasses from agricultural crops (corn cobs, rice husk and sugarcane bagasse) with cartograms for all micro regions at the state of Mato Grosso do Sul, graphics for quantification in the cities where crops production occurs and a table for total energy obtained by conversion processes. For the whole state of MS, Dourados micro region was identified as the most promising for energy in agriculture with three main cities (Dourados, Rio Brilhante and Maracaju), by solid biofuel availability to provide about 11% of the total electrical energy consumption in 2014.

Exergetic analysis can provide useful information as it enables the identification of irreversible phenomena bringing about entropy generation and, therefore, exergy losses (also referred to as irreversibilities). As far as human thermal comfort is concerned, irreversibilities can be evaluated based on parameters related to both the occupant and his surroundings. As an attempt to suggest more insights for the exergetic analysis of thermal comfort, this paper calculates irreversibility rates for a sitting person wearing fairly light clothes and subjected to combinations of ambient air and mean radiant temperatures. The thermodynamic model framework relies on the so-called conceptual energy balance equation together with empirical correlations for invoked thermoregulatory heat transfer rates adapted for a clothed body. Results suggested that a minimum irreversibility rate may exist for particular combinations of the aforesaid surrounding temperatures. By separately considering the contribution of each thermoregulatory mechanism, the total irreversibility rate rendered itself more responsive to either convective or radiative clothing-influenced heat transfers, with exergy losses becoming lower if the body is able to transfer more heat (to the ambient) via convection.