NONLINEAR BEHAVIOR OF A FLEXIBLE SHAFT PARTLY SUPPORTED BY A SQUEEZE FILM DAMPER

High speed rotors pose stability problems, especially when the speed o f rotation increases above a critical speed. In this case; the dynamic behavior of the fluid bearings has an important effect. This study pr esents several models of the dynamic behavior of bearings, taking into account the flexibility of the shaft, The behavior of the squeeze fil m damper is also described. This element provides damping but its beha vior is totally non-linear, An approach for an active squeeze film dam per is presented: a variable clearance squeeze film damper or a variab le viscosity squeeze him damper (feed with electrorheological fluid) i s used to control a flexible shaft. These technologies could be very p romising in the future. (C) 1997 Elsevier Science S.A.