关键词: 油茶果, 脱壳, 接触参数标定, 物料特征, 响应面试验

Abstract: In order to shorten the research and development cycle of seasonal product processing equipment for Camellia oleifera fruit, the discrete element model of camellia oleifera fruit was established and the contact parameters were calibrated by taking camellia oleifera fruit as the research object. The density, water content, Poissons ratio and elastic modulus of camellia oleifera fruit were 973.56kg/m3, 69%, 0.28 and 156MPa, respectively, measured by drainage method, drying method and uniaxial compression test. The contact parameters were calibrated by comparing the results of physical test and simulation test. The collision recovery coefficient, static friction factor and rolling friction factor of camellia oleifera fruit and steel were respectively calibrated by collision bounce test, slope slip test and slope rolling test with the values of 0.576, 0.540 and 0.0077, respectively. The actual stacking angle of 21.21° was obtained through cylinder lifting test and digital image processing. In the simulation test, the contact parameters between camellia oleifera fruit were taken as the test factors, the simulation stacking angle as the index, the steepest climb test was used to find the optimal interval of the significant factors, and the regression model of simulation stacking angle and significant parameters was established in the response surface test. The optimal parameter combination of camellia oleifera fruit contact was obtained after optimization as follows: Collision recovery coefficient 0.467, static friction coefficient 0.534, rolling friction coefficient 0.0080. The optimal parameter combination was used for verification, and the simulation test pile angle was 21.03°. The results showed that the relative error between the simulated pile angle and the actual pile angle after calibration was 0.85%, and the pile shape was consistent. The calibration results were reliable, and could provide theoretical reference for the research and development and simulation optimization of camellia oleifera fruit processing equipment.

Key words: camellia oleifera fruit, hull, contact parameter calibration, material characteristics, response surface experiment