Effects of blade sliding cutting angle and stem level on cutting energy of rice stems

Previous studies highlighted the significance of optimizing the cutting blade for crop harvesting and size reduction. This study investigated the effect of blade sliding cutting angle and stem level on cutting energy of single rice stem using a cutting apparatus that combined with texture analyzer. The cutting energy was determined for four blade angles. The results showed that the average cutting energy was the highest for cutting stem upper level and the lowest for cutting stem lower level. It was found that the peak cutting force per unit stem area decreased with blade sliding cutting angle increased. However, the least average cutting energy was 9.12 J/mm2 of 45° sliding angle when cutting without counter support blade and 32.3% less than that of 60° sliding angle. When cutting with counter support blade, the cutting energy per unit stem area varied from 6.57 to 12.54 J/mm2 as the sliding angle varied from 0° to 60°, whereas the peak cutting force per unit stem area varied from 2.46 to 0.98 N/mm2. It was concluded that the optimal sliding cutting angle was 45° without support blade and 30° with support blade, respectively. The experiments on rice stems in this study indicated that optimization of sliding cutting angle and stem level have a significant effect on cutting energy savings. Also this study emphasized the need to further investigate the effect of the case of more moisture content and cutting speed on the cutting energy to help in selection of optimum cutting speed and harvesting time.