Investigation of mechanical properties of cotton stalk based on multi-component analyses

Abstract

A b s t r a c t. A comprehensive understanding of the uprooting failure mechanism will likely require the accurate characterization of the mechanical properties of cotton stalk. Uprooting failure includes a fractured cotton stalk and peeled phloem sliding along the xylem. The modulus of elasticity of cotton stalk and its tissues (xylem and phloem) were measured using three different modes (tensile, compression and bending), and the reasons for the fractured cotton stalk and the peeled phloem sliding along the xylem were analysed from the perspective of composite mechanics. The results showed that the cotton stalk radially conforms to the properties of the composite with transverse anisotropy. The axial modulus of elasticity was significantly larger than the radial modulus of elasticity (axial modulus of elasticity: cotton stalk is 3181.79 MPa, xylem is 1093.91 MPa, phloem is 249.89 MPa, radial modulus of elasticity: is 91.04 MPa, xylem is 83.77 MPa, phloem is 77.01 MPa). Xylem is the backbone of the stalk that provides 96% of its compressive strength. The direct cause of fractured cotton stalk originated from the load force that exceeded its intrinsic compressive strength. Peeled phloem sliding along the xylem was related for the most part to the different radial modulus of elasticity of the xylem and phloem, and the weak cohesion between these two tissues. Based on the results, some suggestions were provided for the design of a puller.K e y w o r d s: cotton stalk, elastic modulus, composite material, uprooting

Simulation Research on Cotton Stalk Cutting and Crushing Based on ANSYS/LS-DYNA and Field Experiments

“…Then, the complete flexibility matrix could be determined, and the constitutive equation of a cotton stalk could be obtained. With reference to [26], nine independent elastic parameters of cotton stalk materials are shown in Table 1. In addition, the volume of a cotton stalk sample (ideal cylindrical shape) was measured with electronic vernier calipers, the mass was measured with an electronic balance, and the cotton stalk's density was calculated as 489.11 kg/m 3 .…”

The Mechanical Analysis and Comparative Performance Test of the Roller-Type Pulling Mechanism for the Whole Cotton Stalk Pulling Machine

“…It can be used for composting, manufacturing mixed feed, compressed boards, and microwave carbon cracking, thereby comprehensively utilizing renewable agricultural biomass resources. China is the world's largest producer of cotton [1,2] with a unique advantage in cotton resources. The majority of cotton planting in China adopts the mulch-drip irrigation planting mode.…”