旋转颗粒群非平衡流化阻尼减振机理研究

Rotating particle swarm is with non-equilibrium fluidifying characteristic, and the classic representative of the characteristic is the turbinate fluidifying particle swarm. The radial dimension variation of turbinate particle swarm and the barycentric fluctuation of rotating particle swarm give rise to the damping effect displaying stronger tuning property, if incorrectly design, vibration amplitude can be amplified. This project, the research start from flow pattern feature of rotating particle swarm, the influence of non-equilibrium fluidifying characteristic and the characteristic parameter of particle swarm on flow pattern of rotating particle swarm and damping effect are studied for establishing the topological relationship of characteristic parameter to flow pattern to damping effect, and revealing the damping mechanism of rotating particle swarm. Furtherly, theoretical model of damping effect and predicted approach of dynamic responce on rotating particle swarm are establish. The mapping relation of turbinate fluidifying particle swarm radius with rotational speed is study based on non-equilibrium fluidifying characteristic, and discuss the distribution of kinetic energy and generalized temperature of particle swarm for establishing theoretical model of barycentric trajectories and bring to light the non-equilibrium fluidifying characteristic of rotating particle swarm. Moreover, the evolution principle of particle swarm equivalent weight and the fluctuation of damping effect are studied based on the established theoretical model, and establish their relevant adjusting methods which the reaction force with reversed phase to rotating vibration. Then, these technique will promote exploitative efficiency of rotating particle swarm damping technology.

旋转颗粒群具有非平衡流化特征，陀螺状流化颗粒群的径向尺寸变化和当量质心的偏心波动，导致其阻尼效应具有较强的周期调谐作用，使用不当将振动幅度放大。本项目从旋转颗粒群的流态研究出发，研究颗粒群非稳态流化特性以及颗粒阻尼特征参数对颗粒群流态和阻尼效应的影响，构建特征参数——流态——阻尼拓扑关系，从而揭示旋转颗粒群阻尼减振机理，构建旋转颗粒群阻尼理论预估模型和阻尼效应动态响应预估方法。进一步，研究颗粒群陀螺状流化半径与腔体转速之间的映射关系，讨论颗粒群动能分布、颗粒群广义温度，建立当量质量质心运动理论模型，全面诠释旋转颗粒群动态当量质量非稳态特性。同时，采用所建立的理论模型，研究旋转颗粒群动态当量质量波动演化规律及阻尼效应周期性脉动特性，并建立质量偏心动态作用与转子径向振动的对冲调控方法和阻尼效应脉动周期的调控方法，为旋转颗粒群减振技术的高效利用提供理论支撑。

非平衡旋转颗粒群减振技术突破了传统接触型阻尼减振技术的应用受到限制，将颗粒群嵌入到转子结构内部，实现了转子结构无外设的振动控制。然而其减振机理不明，陀螺状旋转颗粒群波动对转子的影响不清。鉴于此，本项目将以旋转颗粒群阻尼减振技术的工程实践应用为最终目标，展开旋转颗粒群减振机理、陀螺状旋转颗粒群阻尼理论建模和动态调控策略的研究，旨在提出一种旋转颗粒群阻尼减振高效应方法。取得的主要成果包括：①研究了旋转颗粒群流态特性及其动态演变规律，揭示了高速旋转颗粒群非平衡流态特征，并根据旋转颗粒群流态研究结论，建立了旋转颗粒群微观力学模型；②研究了旋转颗粒群在各种流态下的阻尼减振作用形式，揭示了旋转颗粒群阻尼减振机理，依据旋转颗粒群的运动特性，将其视作欧拉—欧拉气固两相颗粒流，建立了颗粒阻尼效应理论预估模型，并将理论模型嵌入到有限元软件，实现了旋转颗粒群减振性能的动态预估；③建立了当量质量质心运动理论模型，揭示了旋转颗粒群动态当量质量非稳态特征，通过研究非稳态当量质量偏心运动对转子动态性能的影响，提出了旋转颗粒群减振性能调控方法，并将其应用到印刷机导向辊振动控制中。研究表明：旋转颗粒群呈类气态时减振效果最佳，此状态下颗粒动能较大，陀螺状旋转颗粒群对转子冲击碰撞和摩擦耗能作用效果最佳。