香蕉地机械化深松土机耦合过程解析及其高效减阻优化

Banana field subsoiling is one of the core techniques for promoting conservation tillage in the China tropical agricultural region. Considering the problems of great soil resistance, high energy consumption, low efficiency of current subsoilers, as well as high clay content and compaction of the latosolic red soil in this region, a multi-layer soil model is developed using the discrete element method (DEM) to study dynamic properties of soil particles resulting from subsoilers in the tropical region of China. Micro and macro soil disturbance characteristics in different layers are obtained by the soil dynamic theory combined with the high-speed photography technology. The results will reveal the effects of diverse structures on soil bulk density, compactness, soil disturbance, and soil cutting forces, which will help to understand the mechanisms for reducing the resistance of subsoiler. Furthermore, a vertical subsoiling technique with adjustable soil penetration blade, which can significantly reduce the soil resistance and decrease the energy consumption, is proposed. Through using the DEM-MBD coupling theory and nonlinear finite element method (FEM), a multi-objective optimization model is developed for the vertical subsoilers. The model results will help to better understand the mechanical mechanisms for reduced soil resistances. By studying the performance of banana field subsoilers, a subsoiling scheme suitable for the China tropical agricultural region is proposed to minimize the soil resistance and maximize the banana yield. This provides a theoretical foundation and technological guide for the applications of banana subsoiling techniques. Research results not only lay a substantial theoretical and technological foundation for the design of high-performance subsoilers, but also provide critical information for improving soil environment, increasing banana production, and promoting the sustainable agriculture.

香蕉地深松是推进我国热带农业区保护性耕作研究的关键技术。针对热带农业区砖红壤粘性含量高、质地粘重，深松阻力大、能耗高、效率低等问题，拟在我国热带典型农业区，研究香蕉地土壤颗粒特性，构建离散元三层深松土壤模型；基于高速摄影技术和土壤动力学理论，获取不同位置深松土壤的微观运动和宏观扰动，揭示不同结构对土壤容重、紧实度、土壤扰动量等参数和耕作阻力的影响，阐明深松高效减阻机理，进而提出一种减阻降耗的可调破土刃式垂直深松技术；借助DEM-MBD耦合理论及非线性有限元法，建立可调破土刃式垂直深松机多目标优化模型，阐明机械化深松动态作业机理；开展香蕉地深松作业降阻效应和增产效应的研究，进而提出适合我国典型热带农业区的适宜深松模式。研究成果不仅能为高性能香蕉地专用深松机设计奠定坚实的理论和技术基础，而且是改善耕地质量、提高农业综合生产能力、促进农业可持续发展的重要举措。

针对热带农业区砖红壤粘性含量高、质地粘重，深松阻力大、能耗高、效率低等问题，在我国热带典型农业区，研究香蕉地土壤颗粒特性，构建离散元三层深松土壤模型；基于高速摄影技术和土壤动力学理论，获取不同位置深松土壤的微观运动和宏观扰动，揭示不同结构对土壤容重、紧实度、土壤扰动量等参数和耕作阻力的影响，阐明深松高效减阻机理，进而提出一种减阻降耗的可调破土刃式垂直深松技术；借助DEM-MBD耦合理论及非线性有限元法，建立可调破土刃式垂直深松机多目标优化模型，阐明机械化深松动态作业机理，开展香蕉地深松作业降阻效应和增产效应的研究，进而提出适合我国典型热带农业区的适宜深松模式。在研期间，本项目创新设计了香蕉地滑切减阻式深松机、砖红壤翼型凿式深松机，开展了基于滑切减阻和翼型凿式的深松机理研究，并研制关键部件及其机具，系列机具在海南农场开展试验示范，极大的改善我国典型热带农业区的深松模式，有利的改善了我国典型热带农业区的耕地质量、提高农业综合生产能力，本项目的研究成果为海南热带农业区的机械化提供了技术支撑，为高性能香蕉地专用深松机设计奠定坚实的理论和技术基础，而且也是改善耕地质量、提高农业综合生产能力、促进农业可持续发展的重要举措。