MOISTURE-DEPENDENT PHYSICAL PROPERTIES OF MEDICAL TINY SEEDS: PART A: FLIXWEED (DESCURAINIA SOPHIA L.)

Abstract

Knowledge of agricultural seeds’ physical properties has significant importance for machinery and processing equipment design. Physical properties of flixweed (Descur ainia sophia L.) seeds were determined as a function of moisture content. Several properties were studied in the moisture range from 5.28 to 17.53% dry basis. Also, probability distribution of seeds’ principal dimensions were modeled by Gamma, Generalized Extreme Value, Lognormal, and Weibull functions. With increasing moisture content from 5.28 to 17.53%, properties including; length, width, thickness, geometric and arithmetic mean diameter, sphericity, specific surface area, volume, and projected area showed no specific trend. In contrast, the surface area increased from 6×10-7 to 1×10-6 m2. The bulk and particle density decreased from 696.61 to 542.51 kg·m-3, and 1217.50 to 1189.02 kg·m-3, respectively. The porosity increased from 42.78 to 54.37%. The maximum external static angle of friction belonged to wood at all moisture content levels, followed by the iron and galvanized surfaces. At all moisture levels, the emptying angle of repose was more than the filling one.