土壤-马铃薯块茎-根系团聚体动态破裂特性及其与挖掘铲耦合作用机理研究

项目名称： 土壤-马铃薯块茎-根系团聚体动态破裂特性及其与挖掘铲耦合作用机理研究

项目编号： No.51505305

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 赵萍

作者单位： 沈阳农业大学

项目金额： 21万元

中文摘要： 我国提出马铃薯主粮化战略，但目前收获机械化程度相对较低，并且存在牵引阻力大、伤薯率高等问题，亟待从土壤-块茎-根系团聚体动态破裂流动机理及收获土壤动力学研究获得突破，项目综合考虑马铃薯块茎、根系及周边土壤形态和力学特性差异的影响，利用仿真模拟和田间试验相结合的方法对其进行深入研究。通过试验获得块茎、根系及土壤物理力学特性参数；基于分形理论与实体建模技术，采用有限元和离散元相结合的方法建立稳态土壤-块茎-根系团聚体仿真模型。在此基础上，建立系统动力学仿真模型，通过仿真模拟和田间试验高速摄影技术，揭示挖掘铲作用下土壤-块茎-根系团聚体动态破裂流动机理。通过单因素、多因素仿真试验及回归分析，揭示铲形与参数对牵引阻力及伤薯率的影响规律，分析牵引阻力的时间历程响应，探明挖掘铲与土壤-块茎-根系团聚体动力学耦合作用机理。为研制高性能马铃薯收获机械奠定基础，也为其他块茎类作物收获土壤动力学分析提供借鉴。

中文关键词： 马铃薯收获过程；土壤动力学；离散元法；耦合作用机理；破裂流动特性

英文摘要： Setting potatoes as one of leading food crops was proposed by Chinese government, however, its harvest mechanization degree is relatively low, meanwhile, bigger traction resistance and higher injury rate are found during the harvest process, it demands the breakthrough of dynamic fracture flow mechanism of soil-tuber-root system and harvest soil dynamics，which will be further studied through a method that combines computer simulation and field testing, and considering the differences of shapes and mechanical property of potato tubers, roots and soils in this project. The physical and mechanical properties of potato tuber, roots and soils are studied through experiment. The discrete element and the finite element method are applied to establish the simulation model of soil-tuber-root system based on fractal theory and solid modeling technology. On thsi basis, the system dynamic simulation model is established, and the dynamic fracture flow mechanism of soil-tuber-root system is revealed through simulation experiment field experiment with high-speed photography. The one-factor and multi-factor simulation experiment are did to reveal the influence rules of the digging shovel’s shape and its parameters on traction resistance and injury rate with regression analysis, and analyze resistance-time response, which can ascertain the coupled mechanism of the kinetics between digging shovel and soil-tuber-root system. The successful implementation of this project will provide the theory basis for studying and manufacturing potato harvest machine with the high-performance, and provides reference for soil dynamics analysis on harvest of other root and tuber crop.

英文关键词： harvest process of potato;soil dynamics;discrete element method;coupling mechanism;fracture flow property