Study of a Novel Squeeze Film Damper and Vibration Generator

1999 ◽  
Vol 122 (1) ◽  
pp. 211-218 ◽  
Author(s):  
C. V. Suciu ◽  
O. Bonneau ◽  
D. Brun-Picard ◽  
J. Fre^ne ◽  
M. D. Pascovici
Keyword(s):  
Reynolds Equation ◽  
Industrial Process ◽  
Vibration Damping ◽  
Squeeze Film ◽  
Squeeze Film Damper ◽  
Squeeze Film Effect ◽  
Stiffness And Damping ◽  
Film Stiffness ◽  
Wedge Effect ◽  
Theoretical Results

A novel squeeze film damper and vibration generator (SFD&VG) is proposed as an option in the vibration control field. The SFD&VG can be used as an active squeeze film damper (ASFD) or as a vibration generator (vibrator), for unidimensional vibration damping or generation. The SFD&VG concept is connected with current research to improve a common industrial process—drilling of deep holes. The SFD&VG is based on the variable area of the lubricant film, which allows the development of a variable force, and a change in fluid film stiffness and damping. The analysis is initiated for an elementary configuration of the SFD&VG—the infinite width Rayleigh step case—and then it is developed for an advanced elliptical SFD&VG. The Reynolds equation is solved for both pure squeeze film effect which provides vibration damping, and pure hydrodynamic wedge effect which provides vibration generation. The theoretical part is continued with the SFD&VG dynamic simulation. The SFD&VG experimental device and vibration measurements, performed for the two defined regimes, ASFD and vibration generator, are presented. Finally, the experimental and theoretical results are briefly compared. [S0742-4787(00)05201-2]

Squeeze Film Dampers: Amplitude Effects at Low Squeeze Numbers

1975 ◽  
Vol 97 (4) ◽  
pp. 1366-1370 ◽  
Author(s):  
Martin H. Sadd ◽  
A. Kent Stiffler
Keyword(s):  
Reynolds Equation ◽  
Dynamic Performance ◽  
Squeeze Film ◽  
Periodic Disturbance ◽  
Squeeze Film Dampers ◽  
Parallel Surfaces ◽  
Load Characteristics ◽  
Squeeze Number ◽  
Stiffness And Damping ◽  
Film Stiffness

Gaseous squeeze film dampers are analyzed to determine the effect of periodic disturbance amplitude on the dynamic performance. Both circular and rectangular parallel surfaces are investigated. A solution of the nonlinear Reynolds equation is obtained by expanding the pressure in powers of the squeeze number σ, retaining up to and including terms 0(σ2). The time dependent load characteristics are found. The effect of disturbance amplitude on the film stiffness and damping is given.

Gas Squeeze Film Stiffness and Damping Torques on a Circular Disk Oscillating About Its Diameter

1967 ◽  
Vol 89 (2) ◽  
pp. 219-221 ◽  
Author(s):  
J. S. Ausman
Keyword(s):  
Angular Velocity ◽  
Surface Area ◽  
Reynolds Equation ◽  
Circular Disk ◽  
Squeeze Film ◽  
Stiffness And Damping ◽  
Film Stiffness

A solution of Reynolds’ equation, linearized for small squeeze film motions, is presented which gives the pressure between two disks, one of which is oscillating about its diameter. Integration of the pressure over the surface area of the oscillating disk yields the squeeze film torque acting on it. The stiffness and damping components of this torque are those portions which oppose angular offset and angular velocity, respectively.

Development of an Efficient Oil Film Damper for Improving the Control of Rotor Vibration

1991 ◽  
Vol 113 (4) ◽  
pp. 557-562 ◽  
Author(s):  
Shiping Zhang ◽  
Litang Yan
Keyword(s):  
High Speed ◽  
Porous Metal ◽  
Porous Matrix ◽  
Squeeze Film ◽  
Oil Film ◽  
Squeeze Film Damper ◽  
Outer Race ◽  
Typical Experiment ◽  
Stiffness And Damping ◽  
Film Stiffness

An efficient oil film damper known as a porous squeeze film damper (PSFD) was developed for more effective and reliable vibration control of high-speed rotors based on the conventional squeeze film damper (SFD). The outer race of the PSFD is made of permeable sintered porous metal materials. The permeability allows some of the oil to permeate into and seep out of the porous matrix, with remarkable improvement of the squeeze film damping properties. The characteristics of PSFD oil film stiffness and damping coefficients and permeability, and also, the steady-state unbalance response of a simple rigid rotor and flexible Jeffcott’s rotor supported on PSFD and SFD are investigated. A typical experiment is presented. Investigations show that the nonlinear vibration characteristics of the unpressurized SFD system such as bistable jump phenomena and “lockup” at rotor pin-pin critical speeds could be avoided and virtually disappear under much greater unbalance levels with properly designed PSFD system. PSFD has the potential advantage of operating effectively under relatively large unbalance conditions.

Dynamical Behaviors of Hybrid Squeeze Film Damper for Rotor System Vibration Control

1995 ◽  
Author(s):  
Zhu Changsheng
Keyword(s):  
Rotor System ◽  
Squeeze Film ◽  
Radial Clearance ◽  
Rigid Rotor ◽  
Squeeze Film Damper ◽  
Damping Coefficients ◽  
Dynamical Behaviors ◽  
System Vibration ◽  
Stiffness And Damping ◽  
Film Stiffness

Abstract The behaviors of oil film stiffness and damping coefficients of the deep multi-recessed hybrid squeeze film damper (HSFD) with the orifices compensated are first analysed in this paper. The control ability of the HSFD on the rotor system vibrations is studied theoretically and experimentally with a rigid rotor system supported on the HSFD, and compared with that of the conventional squeeze film damper (SFD). Investigation shows that the HSFD not only can significantly improve the high nonlinearity of the SFD, but also can effectively control the rotor vibrational amplitudes, especially for larger rotor unbalance levels and radial clearance ratios, as compared with the SFD.

Study of Transient Characteristic of a Simple Rigid Rotor Supported on a Squeeze Film Damper With Valvular Metal Rubber Squeeze Film Ring

2007 ◽  
Author(s):  
Yanhong Ma ◽  
Jie Hong ◽  
Dayi Zhang ◽  
Hong Wang
Keyword(s):  
High Speed ◽  
Squeeze Film ◽  
Impact Loads ◽  
Rigid Rotor ◽  
Squeeze Film Damper ◽  
Damping Coefficients ◽  
Metal Rubber ◽  
Stiffness And Damping ◽  
Film Stiffness ◽  
Blade Loss

An efficient oil film damper known as a squeeze film damper with valvular metal rubber squeeze film ring (SFD/VMR) was developed for more effective and reliable vibration control, and especially for improving the blade loss dynamics of high-speed rotors based on the conventional squeeze film damper (SFD). The immobile squeeze film ring of the SFD was replaced by the elastic squeeze film ring with the valvular metal rubber subassembly (VMR) of the SFD/VMR. The squeeze film force properties of the SFD/VMR was improved, because it can passively adjust the squeeze film clearance by taking advantage of the elastic deformation of the VMR and can control the squeeze film clearance in a suitable range. The characteristics of squeeze film stiffness and damping coefficients, as well as the steady-state unbalance response of a simple rigid rotor supported on SFD/VMR and SFD, were reported in a previous literature[1]. In this paper, the transient response of the rigid rotor supported on SFD/VMR and SFD subjected to sudden unbalance of blade loss are inverstigated. Time transient simulation and experimental results indicated that SFD/VMR can operate effectively under much greater unbalance compared with SFD, especially under relative large impact loads of blade loss. The SFD/VMR can suppress the occurrence of the nonlinear vibration phenomenon markedly, such as the bistable jump up phenomenon. Furthermore, the effective eccentricities of SFD/VMR with small transfer ratio (T<1.2) extend to two times of SFD, and optimum film stiffness and damping distribution within the whole film clearance can be achieved.

scholarly journals An Improved Squeeze Film Damper for Rotor Vibration Control: Theoretical Results

1994 ◽  
Author(s):  
J. Y. Zhao ◽  
I. W. Linnett ◽  
E. J. Hahn
Keyword(s):  
Operating Conditions ◽  
Outer Ring ◽  
Squeeze Film ◽  
Squeeze Film Damper ◽  
Constant Stiffness ◽  
Wide Range ◽  
Squeeze Film Dampers ◽  
Secondary Support ◽  
Stiffness And Damping ◽  
Theoretical Results

This paper proposes an improved squeeze film damper which will prevent the bistable operation associated with conventional squeeze film dampers at large unbalances and/or at small bearing parameters. It consists of a conventional squeeze film damper with a flexibly supported outer ring. This secondary flexible support is considered to be massless, and to have a constant stiffness and damping. The effectiveness of this damper in preventing bistable operation is investigated over a wide range of operating conditions for a rigid rotor supported on a centrally preloaded squeeze film damper. It is shown that depending on relevant parameters such as the stiffness ratio between the secondary support and the retaining spring, the damping coefficient of the support, and the mass ratio between the damper outer ring and the rotor, this proposed damper is very effective in preventing bistable operation even for high unbalance conditions.

Pressurized Oil Squeeze Film Dampers

1980 ◽  
Vol 102 (1) ◽  
pp. 41-47 ◽  
Author(s):  
A. Kent Stiffler
Keyword(s):  
Design Methodology ◽  
Squeeze Film ◽  
Rigid Rotor ◽  
Squeeze Film Damper ◽  
Supply Pressure ◽  
Squeeze Film Dampers ◽  
Stiffness And Damping ◽  
Film Stiffness

A pressurized oil squeeze film damper supporting a rigid rotor mounted in antifriction bearings is investigated. Orifice and inherent feed inlets are examined, and it is shown that the clearance determines the inlet resistance for a groove or slot. The film stiffness and damping forces are determined as a function of the restrictor coefficient, rotor unbalance speed and the supply pressure using the short bearing approximation. These forces are related to the system transmissibility. A design methodology for low transmissibilities is presented.

Development of an Efficient Oil Film Damper for Improving the Control of Rotor Vibration

1990 ◽  
Author(s):  
Shiping Zhang ◽  
Litang Yan
Keyword(s):  
High Speed ◽  
Porous Metal ◽  
Squeeze Film ◽  
Oil Film ◽  
Squeeze Film Damper ◽  
Outer Race ◽  
Squeeze Film Damping ◽  
Typical Experiment ◽  
Stiffness And Damping ◽  
Film Stiffness

An efficient oil film damper known as porous squeeze film damper (PSFD) was developed for more effective and reliable vibration control of high speed rotors based on the conventional squeeze film damper (SFD). The outer race of the PSFD is made of permeable sintered porous metal materials. The permeability allows some of the oil to permeate into and seep out the porous matix, with remarkebly improvement of the squeeze film damping properties. The characteristics of PSFD oil film stiffness and damping coefficients and permeability, also, the steady state unbalance response of a simple rigid rotor and flexible Jeffcott’s rotor supported on PSFD and SFD are investigated. A typical experiment is presented. Investigations show that the nonlinear vibration characteristis of the unpressurized SFD system such as bistable jump phenomena and “lockup” at rotor pin–pin critical speeds could be avoided and virtually disappear under much greater unbalance level with properly designed PSFD system. PSFD has the potential advantages to operate effectively under relative large unbalance conditions.

Development of Porous Squeeze Film Damper Bearings for Improving the Blade Loss Dynamics of Rotor-Support Systems

1992 ◽  
Vol 114 (3) ◽  
pp. 347-353 ◽  
Author(s):  
Shiping Zhang ◽  
Litang Yan ◽  
Qihan Li
Keyword(s):  
Squeeze Film ◽  
Rigid Rotor ◽  
Rotor Vibration ◽  
Squeeze Film Damper ◽  
Outer Race ◽  
Squeeze Film Damping ◽  
Rotor Support ◽  
Stiffness And Damping ◽  
Film Stiffness ◽  
Blade Loss

An efficient oil film damper known as porous squeeze film damper (PSFD) is developed based on conventional squeeze film damper (SFD) for more effective and reliable rotor vibration control and especially for improving the blade loss dynamics for rotor support system. The permeability of the outer race of PSFD could remarkably improve the squeeze film damping properties. The transient response of a simple rigid rotor and flexible Jeffcott’s rotor supported on PSFD and SFD subjected to sudden unbalance of blade loss are investigated. Time transient simulation show that PSFD could operate effectively under much greater unbalance as compared with SFD, especially under relative large impact loading of blade loss. Furthermore, the effective eccentricities of PSFD with small transmissibilities (T<1.0) extend to a range of ε<0.9, and optimum film stiffness and damping distribution within the whole film clearance could be achieved.

Ball bearing turbocharger vibration management: application on high speed balancer

2020 ◽  
Vol 21 (6) ◽  
pp. 619
Author(s):  
Kostandin Gjika ◽  
Antoine Costeux ◽  
Gerry LaRue ◽  
John Wilson
Keyword(s):  
Dynamic Behavior ◽  
High Speed ◽  
Internal Combustion Engines ◽  
Ball Bearing ◽  
Squeeze Film ◽  
Design And Technology ◽  
Squeeze Film Damper ◽  
Damping Coefficients ◽  
Bearing Loads ◽  
Stiffness And Damping

Today's modern internal combustion engines are increasingly focused on downsizing, high fuel efficiency and low emissions, which requires appropriate design and technology of turbocharger bearing systems. Automotive turbochargers operate faster and with strong engine excitation; vibration management is becoming a challenge and manufacturers are increasingly focusing on the design of low vibration and high-performance balancing technology. This paper discusses the synchronous vibration management of the ball bearing cartridge turbocharger on high-speed balancer and it is a continuation of papers [1–3]. In a first step, the synchronous rotordynamics behavior is identified. A prediction code is developed to calculate the static and dynamic performance of “ball bearing cartridge-squeeze film damper”. The dynamic behavior of balls is modeled by a spring with stiffness calculated from Tedric Harris formulas and the damping is considered null. The squeeze film damper model is derived from the Osborne Reynolds equation for incompressible and synchronous fluid loading; the stiffness and damping coefficients are calculated assuming that the bearing is infinitely short, and the oil film pressure is modeled as a cavitated π film model. The stiffness and damping coefficients are integrated on a rotordynamics code and the bearing loads are calculated by converging with the bearing eccentricity ratio. In a second step, a finite element structural dynamics model is built for the system “turbocharger housing-high speed balancer fixture” and validated by experimental frequency response functions. In the last step, the rotating dynamic bearing loads on the squeeze film damper are coupled with transfer functions and the vibration on the housings is predicted. The vibration response under single and multi-plane unbalances correlates very well with test data from turbocharger unbalance masters. The prediction model allows a thorough understanding of ball bearing turbocharger vibration on a high speed balancer, thus optimizing the dynamic behavior of the “turbocharger-high speed balancer” structural system for better rotordynamics performance identification and selection of the appropriate balancing process at the development stage of the turbocharger.

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