Vibration Characteristics of Magnetic Nano Fluids-Filled Flexible Cantilevers Under Varied Magnetic Fields

In this paper, the influence of an external magnetic field on the vibration responses and damping ratios of a vascular beam filled with three different magnetic nanofluids are investigated. First, the equation of motion of a fluid-filled beam is derived based on the published works and some amendments are made to simultaneously include the damping ensuing from the surrounding air and also the effects of viscosity of the fluid inside the vascular channel. Then, the effects of an external magnetic field on the viscosity of the fluid is studied and incorporated into the equation of motion of the beam. Finally, based on three magnetic nanofluid samples, simulations are conducted to represent the changes in frequency response functions and damping ratios of the vascular channel beam. The maximum increase observed in the viscosity of the magnetic nanofluid samples under the influence of magnetic field with the intensity of 1 Tesla was 16%, while the reduction in the vibration amplitude found 12.7% and 33.8% for the first and second vibration mode under the influence of the maximum magnetic field intensity of 0.3 Tesla. Moreover, the maximum decrement of the damping ratio was 1.1% under the same magnetic field. However, it seems that the higher values for vibration reduction can be achieved by using the magnetic nanofluid with higher magnetic particle concentrations and viscosities.