1990 年 56 巻 529 号 p. 2367-2372
Electro-Rheological fluid (ERF) has notable characteristics of viscosity which could be applicable for various industrial machines. Viscosity of ERF increases in accordance with the applied electric field. Without an electric field, ERF has the viscosity characteristics of a Newtonian liquid. Variation of viscosity is reversible, and the required time for variation is said to be as short as 0.001 sec. Numerous applications of ERF in the engineering field have been attempted since the characteristics of ERF were discovered by W. M. Winslow. However, no successful application has ever been reported. This paper deals with the successful application of ERF to a squeeze film damper. It is elucidated that the squeeze film damper with ERF is quite effective for the reduction of vibration for any rotor system. First and second critical speeds can be easily passed without large vibration amplitude. It is also shown experimentally that there may be the most effective damping ratios for every mode of the rotor. Transition phenomena of the modes in accordance with supported damping are clarified in the present experiment.