Analysis of the resistance reduction mechanism of potato bionic digging shovels in clay and heavy soil conditions

Abstract

In order to reduce the energy consumption and resistance during the process of potato digging, researchers designed bionic longitudinal wave shovels (B-L-W-S) as biomimetic coupling elements. These shovels were inspired by the corrugated structure found on the surface of earthworms and the ribbed structure on the Chlamys farreri scallop flap. The resistance of B-L-W-S was found to be lower than that of an ordinary flat shovel (O-F-S) through the discrete element analysis. The influence of design variables, namely amplitude (A) and frequency (ω), of the bionic structure on drag reduction performance under different water content (10 %, 35 %) was analyzed through soil tank testing. The experimental results indicate that the drag reduction performance of B-L-W-S is superior when the amplitude A is 2.5 and frequency ω is 0.5, under identical test conditions. The mechanical relationship between soil and bionic element was analyzed using the conservation of kinetic energy law in conjunction with the B-L-W-S operation process in a field experiment. The results demonstrate that the bionic element experiences a higher kinetic energy of soil compared to the ordinary element, resulting in better soil flow. The drag reduction mechanism of the bionic element is also theoretically explained. The drag reduction rate of B-L-W-S was 14.45 %, the potato burial rate was 1.34 %, and the potato damage rate was 0.736 %, which met the technical indicators of potato harvesting operations.