Soil-cutting simulation and parameter optimization of handheld tiller's rotary blade by Smoothed Particle Hydrodynamics modelling and Taguchi method

Abstract Reduction of power consumption of mechanical tilling operation benefits the environment and sustainability of a farming system. Rotary blade is the main tilling part of a handheld tiller, and its shape and parameters directly affect power consumption and performance of a handheld tiller. For purpose of optimization of rotary blade and energy saving for the tilling operation, soil-cutting simulation was performed by means of Smoothed Particle Hydrodynamics (SPH) modelling in this study. Taking cornerite of bending point ( X 1 ), alpha angle ( X 2 ) and bending angle ( X 3 ) as control factors and power consumption ( Y ) as evaluation index, soil-cutting experiments by simulation were conducted according to Taguchi method, and correctness of the simulation was validated by soil bin test. The effects of those control factors on power consumption were investigated. A regression equation of power consumption in terms of control factors and their interactions was obtained. The response surfaces to power consumption as functions of X 1 , X 2 and X 1 , X 3 were plotted. Results showed that: control factors of X 1 , X 2 and X 3 are significant at 0.1% probability level by F test of analysis of variance (ANOVA), with orders of importance as X 1 , X 2 and X 3 ; optimized parameters of the rotary blade are X 1 30°, X 2 52°, and X 3 120°; power consumption of the optimized rotary blade is 0.161 kW, with a 12.40% of power consumption reduction compared with the traditional design.