Mechanical Analysis Of The Tuned Liquid Damper And Application Of The Large Radio Telescope

In this dissertation, considering the nonlinear, large hysteresis, and weak stiffness characteristics of The Cable-cabin System of Five-hundred meter Aperture Spherical Telescope (FAST), the wind-induced vibration is an important factor to the system accuracy, thus the vibration control of the feed cabin is very necessary. In the follows, the research works can be described as.1. A nonlinear equilibrium equation of the cabin-cable system was established, based on which, the cables'lengths and forces are calculated out.2. The basic principle of the Tuned Liquid Damper (TLD) was analyzed. Aiming at the Cable-cabin System of FAST, a ring Tuned Liquid Damper was designed. The equivalent model of the TLD was built, and the complex calculation of the fluid was turned into a spring-quality-damping system. From the relevant fluid knowledge, the natural frequencies of the sloshing liquid were obtained by variational method and Ritz method, and then got the equivalent mass, stiffness and damping of the natural frequencies.3. The damping effect of TLD was proved by simulation calculation and vibration experiment of the Five-hundred meter Aperture Spherical Telescope (FAST) 5m model. Contrast the vibration between cabin with or without TLD, and then found out that viscosity of liquid, liquid filling ratio and cabin position were the influencing factors of the damping effect.