Studying Impact of Moisture, Node Position and Loading Rate of Paddy Straw on its Mechanical Properties

Abstract

In this study, mechanical properties of paddy straw such as bending strength, shear strength and Young's modulus were determined through force-deformation curve using textural analyzer with 50 kg load cell. The mechanical properties were determined at three moisture contents, i.e., 18.4% (M1), 13.5% (M2) and 10.8% (M3), at three node positions, i.e., N1, N2 and N3 and three loading rates, i.e., 25, 30 and 35 mm min-1, respectively. The results revealed that moisture content and loading rate at different node positions significantly (p<0.01) affected the bending strength, shear strength, and Young's modulus of straw, whose values varied from 5.35 to 17.34 MPa, 4.99 to 7.35 MPa, 0.43 to 1.39 GPa, respectively, through N1 to N3 with decrease in moisture content; likewise, other findings also indicated increase in output values on increasing loads through N1 to N3. Cutting force was also significantly affected (p<0.01) by shear angle and moisture content, which varied from 6.39 to 22.9 N, and cutting energy ranged from 142 to 511 J by Straw Management System serrated blade and was found to be minimum at 20° shear angle. The mechanical property of the straw for residue management in the context of cutting force for node position N3 at the initial moisture content was found optimum.