Determining and modeling the physical, thermal and aerodynamic properties of Pinto beans with different water contents

The present study aimed to determine and model the physical (orthogonal axes, circularity, sphericity and apparent specific mass), thermal (thermal conductivity, specific heat and thermal diffusivity) and aerodynamic properties (thermal experimental speed) of beans grains with different water contents. BRS cultivar were used as test crop and properties were investigated with seven water contents (32.9; 28.1; 24.9; 21.9; 18.9; 16.2; 13.6% dry base- d.b.). After data collection, mathematical models were set as experimental data. At the moment of choosing the best model, the following were taken into account: the adjusted coefficient of determination (R²) and average relative error (P). The outcome analysis showed that the orthogonal axes and beans grain circularity are directly proportional to water content reduction. Apparent specific mass decreased and sphericity remained constant, with increase in water content. Thermal conductivity, specific heat and thermal diffusivity decreased by 22.7; 12.7; 14.3%, respectively, when water content decreased from 32.9 to 13.6% d.b. The experimental terminal speed was increased by 15.3% when water content increased. Key words: Size and shape, thermal conductivity, terminal speed, Phaseolus vulgaris.