Abstract
In this paper, we propose a new concept of tuned sloshing damper with variable damping system. This system suppresses sloshing by controlling fluid flow with a baffle plate, which is set in the TSD, and increases damping ratio of sloshing while TSD diffuses the vibration energy. Characteristics of the vibration control performance of TSD are investigated with RMS displacement ratio of structure with control the one against without control. As a result, it is found that vibration displacement of structure is suppressed as damping ratio of sloshing increases by controlling fluid flow.