A Method for the Calculation of Dynamic Response Considering Joint Dry Friction

2013 ◽  
Vol 437 ◽  
pp. 152-157 ◽  
Author(s):  
Rong Qiao Wang ◽  
Wu Lin Si ◽  
Dian Yin Hu
Keyword(s):  
Dynamic Response ◽  
Dry Friction ◽  
Computational Simulation ◽  
Equivalent Linearization ◽  
Friction Damper ◽  
Exciting Frequency ◽  
Vibration Stress ◽  
Nonlinear Force ◽  
Stiffness And Damping Coefficient ◽  
Stiffness And Damping

A method for computing dynamic response considering joint dry friction has been developed based on equivalent linearization and micro-slip model. Computational simulation model was established by linking corresponding contact nodes with Matrix27 elements which simulate additional stiffness and damping effects on structure caused by dry friction nonlinear force. Equivalent stiffness and damping coefficient formula was deduced to calculate real constants of Matrix27 elements. An iterative program was created to compute maximum slip displacements of Coulomb contact nodes on interface and dynamic response and vibration stress were calculated then. An experimental verification has also been carried out which testified the accuracy of the method. Evidently attenuation of vibration is revealed which certifies the effectiveness of joint dry friction damper. Better attenuation effect occurs when exciting frequency is nearer natural frequency.

Numerical Investigation on the Micro-Slip along Friction Interfaces

2011 ◽  
Vol 215 ◽  
pp. 286-290
Author(s):  
Zhi Xin Li ◽  
Shi Ming Ji ◽  
Li Zhang ◽  
Qiao Ling Yuan ◽  
Ming Sheng Jin
Keyword(s):  
Energy Dissipation ◽  
Dry Friction ◽  
Contact Stiffness ◽  
Joint Interface ◽  
Careful Study ◽  
The Finite Element Method ◽  
Interaction Interface ◽  
Stiffness And Damping Coefficient ◽  
Stiffness And Damping ◽  
Dissipation Loss

Damping in built-up structures is often caused by energy dissipation or energy loss due to micro-slip along frictional interfaces interaction, which provides a beneficial damping mechanism and plays an important role in the dynamics vibration behavior of such structures, especially the contact stiffness and damping coefficient accounting for the kinematics joint. A detailed study the mechanics derived from the interaction interface between the different components has some embarrassment. And a careful study on the micro-slip phenomenon has been carried out using the finite element method. A classical joint configuration, the plane translation joint, has been used as the model problems. The focus of this paper is to evaluate the effect of dry friction coefficient, the external mechanics on the damping response of frictional joint interfaces interaction, to understand the evolution of the slip-stick regions along a joint interface during loading, and to quantify the amount of energy dissipation/loss during cyclic loading and its dependence on structural and loading parameters.

Steady-State Dynamic Response of Preisach Hysteretic Systems

2005 ◽  
Vol 128 (2) ◽  
pp. 244-250 ◽  
Author(s):  
P. D. Spanos ◽  
A. Kontsos ◽  
P. Cacciola
Keyword(s):  
Steady State ◽  
Dynamic Response ◽  
Numerical Data ◽  
Harmonic Excitation ◽  
Equivalent Linearization ◽  
State Dynamic ◽  
Hysteretic Systems ◽  
Damping Coefficients ◽  
Stiffness And Damping ◽  
Steady State Amplitude

The goal of this paper is to study the steady-state dynamic response of an oscillator involving a hysteretic component and exposed to harmonic excitation. This is accomplished by using the Preisach formalism in the description of the contribution of the hysteretic component. Two cases are considered. In the first one, the hysteretic component is modeled using a series of “Jenkin’s elements,” while in the second one the same component is modeled by a zero-memory plus a purely hysteretic term. The steady-state amplitude of the response is determined analytically by using the equivalent linearization technique which involves input-output relationships for the equivalent linear system, the stiffness and damping coefficients of which are response-amplitude dependent. The derived results are compared with pertinent numerical data obtained by integrating the nonlinear equation of motion of the oscillator. The analytical and the numerical results are found in excellent agreement and supplement the findings of certain previous studies.

Theoretical Dynamic Analysis of a Cantilever Beam Damped by a Dry Friction Damper

1995 ◽  
Author(s):  
I. Korkmaz ◽  
J. J. Barrau ◽  
M. Berthillier ◽  
S. Creze
Keyword(s):  
Dynamic Response ◽  
Cantilever Beam ◽  
Dry Friction ◽  
Coulomb Friction ◽  
Contact Stiffness ◽  
Temporal Integration ◽  
Element Model ◽  
Friction Damper ◽  
Coulomb Friction Law ◽  
Good Agreement

Abstract The dynamic behavior of a cantilever beam damped by dry friction has been studied The beam is represented partly by its effective modal parameters, obtained from a finite element model. The Coulomb friction law is used and a temporal integration of the dynamic response is performed. A detailed parametric study, highlighting the influence of the static and the dynamic friction coefficients, the viscous damping coefficient, the contact stiffness and the position of the damper along the span, on the dynamic response has been conducted. A better understanding of the damping mechanism by dry friction has been obtained. The numerical results have been compared to experimental results, and a good agreement was found. The results could be applied to a turbine blade with a blade to ground damper.

Steady-State Dynamic Response of Preisach Hysteretic Systems

2005 ◽  
Author(s):  
P. D. Spanos ◽  
A. Kontsos ◽  
P. Cacciola
Keyword(s):  
Steady State ◽  
Dynamic Response ◽  
Numerical Data ◽  
Equation Of Motion ◽  
Equivalent Linearization ◽  
State Dynamic ◽  
Hysteretic Systems ◽  
Damping Coefficients ◽  
Stiffness And Damping ◽  
Steady State Amplitude

The goal of this paper is to study the steady-state dynamic response of an oscillator with a hysteretic component to harmonic excitations. This is accomplished by using the Preisach formalism in the description of the contribution of the hysteretic part. Two cases are considered. In the first the hysteretic component is modeled using a series of Jenkin’s elements, while in the second the same component is modeled by a zero-memory plus a purely hysteretic term. The steady-state amplitude of the response is determined analytically by using the equivalent linearization technique which involves input-output relationships for the equivalent linear system the stiffness and damping coefficients of which are response-amplitude dependent. The derived results are compared with pertinent numerical data obtained by integrating the nonlinear equation of motion of the oscillator. The analytical and numerical results are found in excellent agreement, and supplement the analytical findings of certain previous studies.

Experimental Investigation of Dynamic Normal Characteristics of Machined Joint Surfaces

2000 ◽  
Vol 122 (4) ◽  
pp. 393-398 ◽  
Author(s):  
W. P. Fu ◽  
Y. M. Huang ◽  
X. L. Zhang ◽  
Q. Guo
Keyword(s):  
Experimental Investigation ◽  
Dynamic Characteristics ◽  
Static Pressure ◽  
Dynamic Stiffness ◽  
Relative Displacement ◽  
Test Range ◽  
Joint Surfaces ◽  
Exciting Frequency ◽  
Stiffness And Damping Coefficient ◽  
Stiffness And Damping

This paper presents an experimental investigation on the normal dynamic characteristics of several machined joint surfaces, i.e., the varying principle of the normal dynamic stiffness and damping with exciting frequency, relative displacement and static pre-load under different joint conditions, including joint materials, mediums, machining methods and surface roughness, etc.. The joint parameters are extracted from experimental data by establishing the theoretical model of the joint surfaces, and the mechanism is analyzed qualitatively. The studied results show that, in the test range of this paper, the stiffness and damping coefficient of the joint surfaces increase with the static pre-load; the stiffness for a dry joint is independent of the exciting frequency, while the damping coefficients for both a dry and an oiled joint decrease with the exciting frequency; little relative displacement has no marked effect on the dynamic characteristics. The amount of influence of exciting frequency and static pressure is related to the joint conditions. [S0739-3717(00)00804-7]

scholarly journals Improved Reliability of Bladed Disks due to Friction Dampers

1997 ◽  
Author(s):  
Walter Sextro ◽  
Karl Popp ◽  
Ivo Wolter
Keyword(s):  
Dry Friction ◽  
Three Dimensional ◽  
Line Contact ◽  
Two Dimensional ◽  
Centrifugal Forces ◽  
Friction Damper ◽  
Blade Vibration ◽  
Friction Dampers ◽  
Bladed Disk ◽  
Bladed Disk Assembly

Friction dampers are installed underneath the blade platforms to improve the reliability. Because of centrifugal forces the dampers are pressed onto the platforms. Due to dry friction and the relative motion between blades and dampers, energy is dissipated, which results in a reduction of blade vibration amplitudes. The geometry of the contact is in many cases like a Hertzian line contact. A three-dimensional motion of the blades results in a two-dimensional motion of one contact line of the friction dampers in the contact plane. An experiment with one friction damper between two blades is used to verify the two-dimensional contact model including microslip. By optimizing the friction dampers masses, the best damping effects are obtained. Finally, different methods are shown to calculate the envelope of a three-dimensional response of a detuned bladed disk assembly (V84.3-4th-stage turbine blade) with friction dampers.

Research on Damping Vibration Reduction Design Method of Aeroengine Supporting Structure System

2020 ◽  
Author(s):  
Chao Li ◽  
Binglong Lei ◽  
Yanhong Ma ◽  
Jie Hong
Keyword(s):  
Dry Friction ◽  
Dynamic Stiffness ◽  
Vibration Reduction ◽  
Vibration Response ◽  
Contact Friction ◽  
Friction Damper ◽  
Support Structure ◽  
Response Control ◽  
Structure System ◽  
Supporting Structure

Abstract Typical turbofan engine-support-structure systems having a high thrust-to-weight ratio are light, and the structure primarily comprises a plate and shells. The local vibration response of the support structure is excessively large when different frequency loads are applied. A structural vibration response control method based on dry friction damping is proposed to control the excessive vibration response. A dry friction damper with dynamic suction was designed to enhance the damping characteristics of the rotor supporting structure system in the wide frequency domain, without sacrificing the dynamic stiffness of the structure. The system is designed to effectively control the vibration response of the supporting structure at the working-speed frequency. Through theoretical modeling and simulation analyses, the influence of friction contact and damper structure characteristics on the damping effect is described quantitatively. Furthermore, the design idea and the damping process of the supporting structure are described. The calculation results show that the contact friction of the dry friction damper can consume the vibration energy of the supporting frame. A reasonable design of the contact characteristics and geometric configuration parameters of the damper can further optimize the vibration-reduction effect, and thereby improve the vibration response control design of the supporting structure system of aeroengines.

On the Performance of Wavy Dry Friction and Piezoelectric Hybrid Flexible Dampers

2021 ◽  
Author(s):  
Yaguang Wu ◽  
Yu Fan ◽  
Lin Li ◽  
Zhimei Zhao
Keyword(s):  
Piezoelectric Material ◽  
Dry Friction ◽  
Normal Load ◽  
Harmonic Balance Method ◽  
Element Model ◽  
Total Output ◽  
Friction Damper ◽  
Damping Effect ◽  
Thin Walled Structures ◽  
Friction Plate

Abstract This paper proposes a flexible dry friction plate to mitigate the vibration of thin-walled structures for one resonance crossing. Based on a cantilever beam-friction damper finite element model, the geometry and material parameters of the friction plate are optimized numerically through steady-state response analyses by the widely-used Multi-Harmonic Balance Method (MHBM). In order to further improve the damping effect, piezoelectric material is distributed to the flexible damper, and two types of dry friction and piezoelectric hybrid dampers are explored, namely semi-active and passive, respectively. For semi-active hybrid dampers, piezoelectric material is used as an actuator to adjust the normal load applied to the friction interface in real time, so that the friction damping is improved. For passive ones, piezoelectric material is used as a transducer, which dissipates the strain energy stored in the wavy plate by the shunting circuit, additional shunted piezoelectric damping contributes to the total output damping accordingly. Better damping effect compared with the friction baseline is realized for the two types ideally. This damping module has a simple structure and avoids the problem of installation and maintenance of piezoelectric material which is generally bonded to the host structure. Technical challenges are: the semi-active type requires excessive voltage applied to the piezoelectric actuator, while the passive one needs to connect a programmable synthetic circuit.

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