A study of some hydro-aerodynamic properties of snake gourd (Trichosantescucumerina l) seed, kernel and chaff.

The design of pneumatic conveying systems, fluidized bed dryer and cleaning of the agricultural product from foreign materials requires the knowledge of aerodynamics properties of the product. With the increase in the importance of snake gourd as a source of nutrients, oil and industrial material, mechanization of the seed production and processing is currently needed to provide information for the proper design of the handling equipment. Terminal velocities and drag coefficient of snake gourd seed, kernel and chaff were experimentally measured at four moisture content (6.8, 8.6, 12, and 14 %) by suspending the snake gourd seed, kernel and chaff in air stream. A wind tunnel purposely designed for this experiment was used for the measurement of the terminal velocity. The result shows that an increase in moisture content from 6.8 to 14 % db increased the terminal velocity from 2.45 to 3.98 m/s for seed, 2.21 to 3.09 m/s for kernel and 1.35 to 1.77 m/s for chaff. While the increase in the moisture content in the same range increased the drag coefficient of seeds from 2.24 to 13.95 and 2.35 to 9.00 for kernel. The result of the experiment was statistically analyzed using two-way ANOVA. Effect of moisture content was found to be significant over all the parameters investigated at 0.05 % probability. For air separation/cleaning of snake gourd seed the air speed should be less than 2.4 m/s while for designing the cleaning chamber of a snake gourd decorticating machine to separate chaff from kernel after dehaulling process, the air speed should be less than 2.2 m/s but higher than 1.77 m/s.