Abstract—This research was to study the physical, mechanical and aerodynamic properties of sorghum. The moisture contents of sample for 5 levels were in the range of 9.06 to 29.15 % wet basis. Each moisture content level, fifty grains were sampled. The results found that the increase in moisture content resulted in the increasing of grain width, length, thickness and geometric diameter which in the range of 3.86 to 4.16 mm, 4.45 to 4.65 mm, 2.49 to 2.72 mm and 3.50 to 3.75. mm, respectively. In addition, the sphericity, the thousand grains mass and surface area were in the range of 0.79 to 0.81, 23.37 to 28.58 g, and 38.44 to 44.07 mm2, respectively. The porosity and angle of repose were found to increase from 35.15% to 36.75%, and 20.04° to 26.82°, respectively. The bulk and true density decreased from 815.40 to 712.60 kg/m3, and 1257.33 to 1126.72 kg/m3. The coefficient static friction on acrylic, wood, zinc and iron were in the range of 0.25 to 0.48, 0.40 to 0.48, 0.21 to 0.42 and 0.32 to 0.43, respectively. Terminal velocity and the drag coefficient were in the range of 8.54 to 9.73 m/s and 0.32 to 0.34.

Index Terms—Angle of repose, bulk density, coefficient of friction

Cite: Nattapol Poomsa-ad, Lamul Wiset, and Wasan Duangkhamchan, "Effect of Moisture Content on Physical and Aerodynamic Properties of Sorghum," Journal of Medical and Bioengineering, Vol. 3, No. 3, pp. 167-170, September 2014. Doi: 10.12720/jomb.3.3.167-170