Dynamic characteristics of elastic ring squeeze film damper

Abstract

Purpose The purpose of this paper is to present a numerical model to investigate the dynamic behavior and force coefficients of a compact squeeze film damper with dual film clearances adjusted by an elastic ring, known as elastic ring squeeze film damper (ERSFD). Design/methodology/approach The governing equations of ERSFD as well as the boundary conditions are obtained based on Reynolds equation. A simplified Greenwood–Williamson model is implemented to investigate the contact behavior between the elastic ring and the journal. The interactions between the films and the elastic ring are achieved by block iterative method. Findings The radial deformation as well as velocity of the elastic ring are captured to illustrate the pressure profiles of the inner and outer films. High-order frequency components related to the number of the boss N are observed on the frequency spectrum of the film force. The force coefficients of the ERSFD are constant for a wider range of non-dimensional whirling radius ε compared with conventional squeeze film damper. Originality/value The force coefficients of the ERSFD are obtained by assuming that the journal center moves in a circular centered orbit. High-order frequency components related to the number of bosses N are observed. These findings may provide helpful materials for the application of the ERSFD.

Analysis on Influences of Squeeze Film Damper on Vibrations of Rotor System in Aeroengine

“…When the back fulcrum is set with SFD, it is known that the stiffness and damping of SFD have nonlinearity [3], and its typical stiffness and damping curves are shown in Figure 10.…”

“…When the back fulcrum is set with SFD, it is known that the stiffness and damping of SFD have nonlinearity [3], and its typical stiffness and damping curves are shown in Figure 10. Under the condition of high speed and large unbalanced mass, such as rn = 12,800 r/min, which is higher than the second-order critical speed, me = 4 × 10 −4 kg•m, the calculated rotor vibration response is shown in Figure 11.…”

“…In Refs. [2,3], the fluid-structure coupling dynamics of SFD is analyzed by the finite difference method. The direct stiffness and damping coefficients and the cross stiffness and damping SFD are introduced to establish the corresponding dynamic differential equation according to the typical structure and dynamics, particularity of the aeroengine rotor system.…”

Numerical and Experimental Investigation of the Effect of Cavitation on Dual Clearance Squeeze Film Damper

“…e squeeze film damper (SFD) has attracted much attention for its good performance in vibration mitigation. In recent years, the relevant studies have focused on the following issues: the characteristics of nonlinear vibrations of a rotor supported on SFD [1,2], methods of modeling the SFD by considering the effects of fluid inertia [3][4][5][6][7], and the cavitation, the fluid-structure interference, and the structural innovation [8][9][10][11]. For example, Chen et al [1] found that the rotor-SFD system was sensitive to the ratio of two excitation frequencies acted on the rotor system and the influence of fluid inertia becomes greater with the Reynolds number [5].…”

Dynamic analysis of an elastic ring squeeze film damper supported rotor using a semi-analytic method

“…Using squeeze film dampers (SFDs) in controlling the vibration of rotor systems has been common in aero engines. Compared with traditional SFDs, the merits of elastic ring squeeze film dampers (ERSFDs) are their small size and light weight (Chen et al, 2016;Han et al, 2019;Lei, 2006;Siew et al, 2002;Wang et al, 2017;Wang et al, 2018;Wang et al, 2019;Zhang & Ding, 2015). In addition, ERSFDs have an enhanced ability to suppress oil film nonlinearity.…”