Contact Parameters of Liver Particle Accumulation Flow in the Cavity of a Pulverizer / 医用生物力学

ABSTRACT

Objective To calibrate contact parameters of liver tissue discrete element model. Methods Based on MATLAB image processing technology, the accumulation angle of liver tissues was measured. The ‘Hertz-Mindlin with JKR’ contact model was used to simulate the accumulation angle of liver tissues. The orthogonal experiment was designed with the coefficient of rolling friction and the energy of JKR surface as factors. The parameters of the contact model were calibrated by batch processing, and the optimal parameter combination was verified by secondary simulation calibration. Results The accumulation angle obtained by the physical test was 11.2°±0.86°. In the orthogonal experiment, the accumulation angle of the 6th set of parameter combinations was 11.8°, and the relative error was 5.1%. The simulation test and the physical test had a high similarity in accumulation angle and shape. The sequence of factors affecting the accumulation angle was the JKR surface energy between the tissue particles and the stainless steel plate > the rolling friction coefficient between the tissue particles and the stainless steel plate > the JKR surface energy between the tissue particles and the tissue particles=the rolling friction coefficient between the tissue particles and the tissue particles. Conclusions The optimization parameter could be used to further conduct the discrete element simulation between the tissue particles and the pulverizer, so as to reveal the accumulation and flow state of the tissue particles under the action of myoma pulverizer.