移动质量简支梁耦合时变系统建模与实验设计

建立了移动质量简支梁耦合时变系统的动力学模型,通过数值仿真分析了移动质量速度及加速度对耦合时变系统模态参数的影响,得到移动质量诱导产生的附加阻尼。设计并搭建移动质量简支梁实验系统,通过参考实验得到实验系统的初始阻尼,并分别采用频域和时域模态参数辨识方法对质量块不同移动速度下的实验系统进行辨识。结果表明,所建立动力学模型能够对移动质量问题进行准确描述,实验系统可为时变结构动力学分析的理论研究提供实验支持,特别是对时变结构模态参数辨识方法进行实验验证。

Modeling and Experimental Design of the Coupled Moving-Mass and Simply Supported Beam Time-Varying System

A structure with a mass moving on it constitutes a classical coupled time-varying system. A dynamic model of a coupled moving-mass and simply supported beam time-varying system is built. The influence of the moving-mass velocity and acceleration is analyzed, and the damping induced by the moving mass is obtained through numerical simulation. An experimental system consisting of a simply supported beam and a moving mass sliding on it is set up. The initial damping of the experimental system is determined based on the baseline experiment. Different modal parameter estimation methods in the frequency and time domain are employed to estimate natural frequencies of the experimental system with different moving-mass velocities. The results indicate that the dynamic model can accurately describe the moving mass problem. This experimental system can be used to validate theoretical studies on dynamics, especially the modal parameter estimation of time-varying structures.