橡胶输送带动力学参数变化机制与能耗机理研究

The key job to reduce the operation energy consumption of the belt conveyors is developing the energy-saving conveyor belt, the current operation resistance model of the conveyor belt can not reveal the energy consumption mechanism comprehensively, which hinders the development of the energy-saving conveyor belt. In this project, the mechanical property of the rubber conveyor belt is divided into the transition state and the stable state; combining the polymer mechanics, the structural dynamics, the viscoelastic creeping mechanics and the experiments, the constitutive model for the two states of the conveyor belt are researched, the dynamics parameters variation mechanism is revealed, and the transformation criterion for the two states of the conveyor belt is specified; applying the structural dynamics and the viscoelastic mechanics, and combining the working condition variation law of the conveyor belt, the structural damping and the energy consumption under the tensional state and the deflected state are studied; applying the experiments such as realizing the dynamic load by the electronic controlled hydraulic cylinder to simulate the tension of the conveyor belt to validate the energy loss model and reveal the energy loss mechanisms of the tension and the deflection of the conveyor belt. Applying the motion thin plate theory, the damping and the energy consumption of the conveyor belt supported by the rollers of the groove type under the coexistence of the viscoelasticity and the creepage are researched, the energy consumption model is validated by applying the validation experiments such as adjusting the on-line movement speed, and the energy consumption mechanism of the conveyor belt under the contact between the conveyor belt and the rollers is revealed; the result of this project would provide the theory basis for the development of the energy-saving conveyor belts and the design of the related flexible transmission systems.

研发节能型输送带是降低带式输送机运行能耗的关键，现有输送带运行阻力模型没能全面的揭示能耗机理，阻碍了节能输送带的研发进程。本项目将橡胶输送带的力学特性划分为过渡态和稳定态，应用高分子材料力学、结构动力学、粘-弹-蠕性力学与实验研究相结合的方法，研究输送带在两种状态下的本构模型，揭示其动力学参数变化机制，制定两态转变判据；应用结构动力学、粘弹性动力学理论，结合输送带的工况变化规律，研究其拉伸状态、弯曲状态下的结构阻尼和能耗，采用电控液压缸动态加载，模拟输送带张力等实验方法验证能耗模型，揭示输送带拉伸、弯曲能耗机理；采用运动薄板理论，研究粘-弹-蠕共存输送带在槽型托辊支撑下的阻尼和能耗问题，采用运行速度在线可调等实验方法验证能耗模型，揭示输送带与托辊接触过程能耗机理；为研发节能型输送带及相关柔性传动系统设计提供理论依据。

运用微分几何理论，构建了钢丝绳橡胶输送带宏、细观三维参数化模型，在此基础上，采用静力学理论建立了钢丝绳等效弹性模量预测模型，并通过实验对钢丝绳的弹性模量进行实验测量，验证了等效弹性模量预测模型的正确性。采用复合材料力学和粘弹性力学理论，提出由钢丝绳广义Maxwell模型和橡胶基体三元件固体模型并联组合得到钢丝绳芯橡胶输送带的混合本构模型，推导了应力解析解，再采用反演变换建立本构动力学参数的辨识模型，并通过实验对辨识模型进行了验证，揭示了不同加载条件下动力学参数的变化规律。基于热粘弹性动力学理论，提出一种考虑温度的三元件固体模型，通过对变温条件下的动态加载实验参数拟合，构建了输送带变温本构模型参数预测公式。采用果蝇优化算法对RBF网络的扩展参数进行全局优化，再对不同激励下输送带恢复力模型系数进行预测，最后通过实验对神经网络预测结果进行验证，获得了输送带动力学参数预测模型。根据橡胶输送带的松弛、时变特性对输送带动力学参数的过渡态和稳定态进行定义，推导出动应变作用下输送带的应力解析解，并根据解析解中衰减项的特征，对过渡态和稳定态进行分析，建立输送带标准固体模型参数的通用辨识模型和简化辨识模型，最后对钢丝绳输送带进行动应变加载实验，得出：可将通用模型辨识结果与简化模型辨识结果首次达到吻合时的循环加载次数或对应的加载时间，作为划分输送带动力学参数过渡态和稳定态的判别条件。以建立的输送带本构模型为基础，采用粘弹性力学理论对托辊与输送带间动态接触特性进行了分析，推导了输送带全厚度方向的压陷阻力计算方程，并通过实验对方程进行了验证，揭示了橡胶输送带的阻尼能耗机理；在上述研究成果基础上，采用机械系统动力学理论构建了大型带式输送机系统动力学方程，通过数值求解获得了沿输送带线路上不同位置处胶带拉伸能耗的分布规律。根据理论研究成果进行了输送机节能运行控制系统的研发。