基于尺度效应和碎裂损伤效应协同的褐煤脱水过程复合能量场耦合机制

褐煤高含水限制了其直接利用，而现有褐煤干燥技术存在能耗高这一突出问题，原因在于现有干燥技术形式单一、强度固定的特性与高效干燥过程对复合能量场非线性输入需求之间存在矛盾，因此构建复合能量场非线性干燥过程成为突破褐煤高效干燥技术瓶颈的关键。本项目拟以低能耗驱动下褐煤干燥尺度效应与碎裂损伤效应协同关系为复合能量场耦合基础，以褐煤干燥过程的应力响应-应力叠加-床层演变-效应协同-能量耦合为思路开展科学研究。拟探明复合能量场下褐煤结构的应力动态响应与叠加效应，阐明复杂内外应力场下褐煤多元异质结构损伤碎裂行为及演变规律，揭示复合物理场下褐煤颗粒群尺寸时空演变规律与热质传递行为；明晰褐煤干燥尺度效应和碎裂损伤效应的协同关系，建立温度场-扩散场-应力场耦合本构模型；探究热-微波-机械能量场耦合作用与过程调控机制，构建复合能量场褐煤非线性干燥过程和技术原型，为突破褐煤大规模高效干燥的技术瓶颈提供理论基础。

The direct utilization of lignite is seriously limited by its high moisture content, and high-efficient drying method is becoming the key to the utilization of lignite. Due to the contradiction between the requirement of non-linear input of multi-energy fields and the intensity of fixed energy field with single form in lignite drying, the construction of non-linear drying process of multi-energy fields is the key to breaking through the bottleneck of high-efficient drying process. In this project, the synergy between scale effect and fragmentation effect of lignite drying driven by low energy consumption is considered as the coupling mechanism of multiple energy fields, and the scientific research will be carried out based on the idea of stress response, stress superposition, drying bed evolution, synergistic effect, and energy coupling in lignite drying under multi-energy fields. The major contents will be involved in dynamic stress response and superposition effect of lignite structure under multi-energy fields, the evolution of damage and fragmentation of lignite under internal and external stress fields, temporal and spatial evolution of particle size and the behavior of unsteady heat and mass transfer in lignite under multi-physical fields. In addition, it is essential to study the synergistic relationship between scale and fragmentation effect in lignite drying, so as to build a coupled constitutive model of temperature field, diffusion field and stress field. Finally, based on the coupling effect of thermal, microwave, and mechanical energy fields and process control mechanism, the non-linear drying process of lignite in multi-energy fields is going to be constructed, which can provide theoretical basis for the breakthrough of the technical bottleneck of large-scale and efficient drying of lignite.