Invesrigation of aerodynamic properties of soya seed varieties in Golestan province

Terminal velocity and drag coefficient are the most important aerodynamic properties of agricultural products like soya in the designing of machines and processing equipment. In this study, these properties were evaluated for three soybean varieties (Sahar, Viliyams and Dpx) and five moisture content levels (4, 8, 12, 16 and 20% d.b.). First, relation of the terminal velocity and the drag coefficient with the moisture content was mathematically formulated, and then, in fluidized bed dryer was practically investigated. The results showed, with the changing of the moisture content of three varieties (Sahar, Viliyams and DPX) from 4% to 20%, the terminal velocity of three varieties increased respectively from 4.42 to 5.1, 5.12 to 5.94 and 4.71 to 5.5 (m/s) while at the same moisture content the drag coefficient decreased from 0.45 to 0.389, 0.53 to 0.452 and 0.512 to 0.444. The diagrams of the terminal velocity and the drag coefficient revealed that the terminal velocity and the drag coefficient values have a linear relationship with the moisture content, but with increasing the moisture content, terminal velocity values increased whilist drag coefficient ones decreased.