Optimized modeling and experiment test of a fluid inerter

This paper presents the fluid structure of the third passive vibration isolation element inerter. The fluid inerter ideally has the same characteristic that the force applying to the two terminals is proportional to the relative acceleration as the ball-screw inerter and rack-and-pinion inerter. An optimized nonlinear model of the fluid inerter is introduced, and the effect of nonlinearities compromising friction, oil density and viscosity of the fluid are discussed and analyzed. Simulations show that the friction has a great effect on the dynamic performance of fluid inerter in low frequency and the influence of the viscosity is not negligible. The damping force and the inertia force will become larger with the increase of the frequency and the inertia force will become more and more apparent in higher frequency. Furthermore, experiments are carried out to test the effectiveness of the fluid inerter. Results show that the optimized nonlinear model of the fluid inerter is deemed effective