PHYSICAL, MECHANICAL AND AERODYNAMIC PROPERTIES OF JATROPHA SEEDS

This study was conducted to investigate physical, mechanical and aerodynamic properties of Jatropha seeds cultivated in Egypt. The properties were determined at moisture content of Jatropha seed 8.25 (%, d. b.). The results showed that the mean values of the %-ages by weight of seed parts to whole seed was 60.84 and 39.16 % for kernels and husks, respectively. The results also include the following properties; length, width, thickness, arithmetic and geometric mean diameter, sphericity, aspect ratio, mass of individual seed, thousand seed mass, true density, bulk density, porosity, surface area, specific surface area and projected area; their averages were found to be 17.28 mm, 11.06 mm, 8.11 mm, 12.15 mm, 11.57 mm, 67.05 %, 64.18 %, 0.598 g, 551.1 g, 0.713 g/cm^3, 0.425 g/cm^3, 39.89%, 421.6 mm^2, 3.08 cm^2/cm^3 and 154.4 mm^2, respectively. The mean value of angle of repose was 0.466 rad. For the coefficient of static friction; the stainless steel surface had the lowest value (0.196) while; the Plexi-glass surface had the highest value (0.403). The highest values of the rupture force, deformation ratio, hardness and the energy needed for rupture force were 101.3 N, 0.13, 105.17 N/mm and 61.7 N.mm while; The lowest values were 57.0 N, 0.05, 99.17 N/mm and 19.1 N.mm, respectively. The average values of terminal velocity and coefficient of drag were 14.27 m/s and 0.30, respectively. Also; the average value of Reynolds number was 10898 therefore; the pattern of air flow is turbulent.