Energy Dissipation of Tuned Magnetic Fluid Rolling-Ball Damper in Low-Frequency Vibration

For the low-frequency vibration in high-rise structures, typical passive dampers struggle to cope with the complex and changing environment, and the magnetic fluid with magnetically susceptible could provide a new avenue for addressing this issue. Utilizing current modulation, the semi-active tuned magnetic fluid rolling-ball damper (TMFRBD) can adjust its frequency. This study focuses on energy dissipation, and the energy dissipation model is theoretically derived; experimental comparisons are made between the TMFRBD and the tuned fluid rolling-ball damper in terms of vibration reduction and energy dissipation rates. According to the results, the tuned fluid rolling-ball damper can only reduce the amplitude by roughly 12%, but the TMFRBD can do so by about 21%. The displacement time history displays the "frequency shift;" however, the "frequency shift" has no impact on damping capabilities, and the entire structure continues to have a positive damping state. Similarly, the tuned fluid rolling-ball damper can only dissipate 18% of the energy, and the TMFRBD can dissipate roughly 38% of the energy. Magnetic fluid can achieve the purpose of tuning control, and the viscosity can further reduce the displacement response of the structure under tuning conditions. This work demonstrates the importance of TMFRBD in the low-frequency vibration of high-rise structures and supports the notion that magnetic fluid is a smart material.