The major selfexcited vibration mechanisms in the systems with friction can be categorized into three types. Friction is examined from a control system design perspective in 7. However, stability does not improve under normal highfrequency excitations, though amplitude of the selfexcited oscillation can be controlled to some extent. Modeling method associating generalized polynomial chaos expansion and kriging for mechanical systems. Nonlinear control of frictioninduced selfexcited vibration. Study of friction induced stickslip phenomenon in a minimal.
Selfexcited vibrations are analyzed on the basis of the experimental data. Friction contact, frictioninduced vibrations, selfexcited systems. In 1, 6 it has been analyzed a system with one degree of freedom in. The numerical method used here is the direct numerical integral method as we have presented previously, which is a shooting method able to obtain highly accurate periodic solutions of systems with. The formulation accounts for the coupling between the axial and angular. Index terms self excited vibrations, dry friction, friction instability, limit cycle, stickslip. The structural model is obtained from the measurement of the modal frequencies and damping ratios of three degrees of freedom. Frictioninduced oscillations of a nonasbestos organic. This paper investigates frictioninduced selfexcited vibration in a bistable. Frictioninduced vibrations, a type of selfexcited oscillation refer to 1, 2, are a frequently. Numerical modeling of frictioninduced vibrations and dynamic instabilities. Introduction t he dynamic behavior of many tribomechanical systems is in. A nonlinear friction work formulation for the analysis of selfexcited vibrations.
Non smooth contact dynamics approach for mechanical. Dry friction induced self excited vibration between sealing disc and pipe is the source of chatter vibration on pig, and lead to the wear of pigs sealing disc in natural gas pipeline. An analysis of the selfexcited torsional vibrations. Selfexcited vibrations are observed in many technical applications. One of the typical vibration problem by friction is selfexcited vibration due to. Selfexcited oscillations in sliding with a constant friction coefficienta simple model.
International journal of mechanics instability induced by. However, stability does not improve under normal highfrequency excitations, though amplitude of the self excited oscillation can be controlled to some extent. Friction induced vibrations in railway transportation. Forced selfexcited vibration with dry friction applied. So, the system, which is under the self excited vibrations begin to vibrate of their own accord in. Mechanics and nonequilibrium thermodynamics of sliding contact combines the mechanical and thermodynamic methods in tribology, thus extending the field of mechanical friction induced vibrations to nonmechanical instabilities and self organization processes at the frictional interface. A selfexcited autoparametric system with dry friction. The investigation of the influence of dynamics parameters on. Selfexcited vibrations induced by dry friction, part 2. Vibration analysis of multi degree of freedom selfexcited systems. Vibration analysis of multi degree of freedom selfexcited.
Journal of sound and vibration 1990 72, 177190 selfexcited vibrations induced by dry friction, part 2. An experimental investigation was conducted in the laboratory with a pinondisk type sliding apparatus to study selfexcited vibrations induced by dry friction. Elimination of frictioninduced vibration of a propulsion. When the normal load is further increased, selfexcited periodic vibrations are produced. Dweib, selfexcited vibrations induced by dry friction. Typically, high frequency squeal occurs in the frequency range from 8 to 16 khz, while low frequency squeal from 1. Experimental investigation on the avoidance of selfexcited. Interactions among friction, wear, and system stiffness. If the inline pdf is not rendering correctly, you can download the pdf file. The in uence of the interface coe cient of friction upon. For dry and wet weather conditions in the wheelrail zone parameters of eq. A comparative study on the control of frictiondriven. Frictioninduced vibration in a bistable compliant mechanism mdpi. Some mechanical systems have frictional joints where one surface slides on another with dry friction.
This leads to occurrence of selfexcited vibrations in tread brake unit or simply brake block. Analytical approaches for friction induced vibration and. The cause of vibrations is a nonlinear and unknown friction between a drill string and the environment, containing jumps in its characteristics. We conduct experimental study of friction induced oscillations in a nonasbestos organic material steel pair used in disc brakes of motor vehicles. Prevention methods of self excited vibration due to dry friction of vertical rotor yusuke watanabe1, masaji ishii1 isromac 2016 international symposium on transport phenomena and dynamics of rotating machinery hawaii, honolulu april 1015, 2016 abstract recently, because of performance upgrades of rotating machinery, the clearance between. Self excited vibrations caused by dry friction, which is generally expressed as a function of relative sliding velocities between two solid bodies, are analysed theoretically and observed experimentally. As explained above, selfinduced vibrations occur when the friction coefficient decreases while engaging during the slip phase with increasing slip speed in the friction contact. Self induced chatters friction vibrations pressure induced chatters the self induced chatter is caused by a friction coefficient change with regard to the slip speed. Study of friction induced stickslip phenomenon in a. Statistics of complex eigenvalues in frictioninduced. Pdf analysis of selfexcited vibration due to dry friction in a system. Frictioninduced vibration of a lubricated mechanical system.
On the periodic response of a harmonically excited dry friction. Investigation of selfexcited vibrations in tread brake. Liu, wang and chen 4 investigated it with nonlinear vibration theory, by modeling and analyz ing the selfexcited vibration phenomenon 5 caused by dry friction of both the shell. Selfexcited vibrations during engagements of dry friction. It is thought that this design guides may be useful in the control and reduction of the vibrations induced by dry friction. Selfexcited vibrations induced by dry friction, part 1. The nonlinear vibration theory and the experimental modal analysis are used in this paper to study the self excited vibration of the shellliquid coupled system induced by dry friction. Analytical approaches for friction induced vibration and stability analysis anooshiravan farshidianfar a. This article presents an overview of the acoustics of friction by covering friction sounds, frictioninduced vibrations and waves in solids, and descriptions of other frictional phenomena related to acoustics.
Self excited vibrations during engagements of dry friction clutches 982846 during the starting of the vehicle, the friction clutch engagement sometimes generates judder. Friction, resulting from the sliding contact of solids, often gives rise to diverse forms of waves and oscillations within solids which frequently lead to radiation of sound to the. Stickslip vibrations induced by alternate friction models. Verification of the friction coefficients determining. On selfexcited vibrations due to sliding friction in systems of deformable bodies general formulation and influence of contact properties, proceedings of the 7th euromech solid mechanics conference, lisbon, 2009. Long after early theoretical predictions of self excited vibration limit cycles by poincar6 and lyapunov minorsky, 1947 postinstabilitythreshold limit cycles offluid induced, self excited lateral vibrations ofrotors havebeendiscussed by. Highorder selfexcited vibration induced by dry friction.
A selfexcited autoparametric system with dry friction has been submitted to journal. For example, the mathematical model of selfexcited vibrations, induced by dry friction, requires a nonzero slope of friction characteristic in order to initialize such kind of oscillations babakov 1968. Suppression of selfexcited vibrations in rotating machinery. The effect of dry friction stickslip coefficients and rubbing velocity on self excited vibration, and the limit cycle and hopf bifurcation solution of the system are obtained. Selfvibrationinduced wear of a friction pair nasaads. A new efficient adaptive control of torsional vibrations. Liu, wang and chen 4 investigated it with nonlinear vibration theory, by modeling and analyz ing the self excited vibration phenomenon 5 caused by dry friction of both the shell. Considering its occurrence from the historicalpoint of view in the last. The formulation accounts for the coupling between the axial and angular motions by. Selfexcited oscillations in sliding with a constant friction. Reliable prediction of frictioninduced unstable vibrations such as in brake squeal or hip squeak remains a challenge because of nonlinearities involved and because the complex eigenvalue analysis cea widely. Nonlinear behaviour of the friction coefficient results in selfexcited vibration and causes undesirable stickslip oscillations. Frictional contacts are often involved in the mechanism which generates vibrations. Combining theoretical and experimental modal analyses on selfexcited vibration induced by dry friction between two elastic structures, we can explain the highorder sell excited vibration phenomenon in which water droplets spurt from fourteen or twelve areas of the chinese culture relic dragon washbasin when it is rubbed with hands, and clarify the mechanism of the singular highorder.
Friction induced vibrations of a two degrees of freedom system. This paper focuses on the problem of eliminating self excited vibration in a propulsion shafting system induced by the friction of the waterlubricated rubber bearing. Conceptually, frictioninduced vibration can be accomplished only when forceoscillations are accompanied by motion oscillations along the direction of the force oscillations with a suitable relative phase. These vibrations are often encountered in practice, with detrimental effects such as excessive wear of components, surface damage, fatigue failure and noise generation.
This classical friction model does not explain all dynamical behaviour observed in mechanical systems with friction. The classical single degreeoffreedom massonmovingbelt model describing frictioninduced vibration is considered, which is generally used to study the. Dweib department of mechanical and aerospace engineering, illinois institute of technology, chicago, illinois 60616, u. The intensity of selfexcited vibration is often so high that a save run is impossible and can result in a failure. Received 3 january 1989 some mechanical systems have frictional joints where one surface slides on. A lumped parameter model is presented for studying the dynamic interaction between two disks in relative rotational motion and in friction contact. The braking force that slows down the railway vehicles is associated with dry sliding friction between the brake pads and the wheels. This study deals with a forced selfexcited vibrating system accompanied by dry friction as an example of a nonlinear system with discontinuities. Transition to fluidinduced limit selfexcited vibrations of. On the periodic response of a harmonically excited dry. That means, all type of brake noise originates as a selfexcited oscillation which is the stickslip phenomenon. The friction coefficient gradients of todays facings lie between. Selfexcited oscillations in sliding with a constant.
Tribology in industry experimental study of frictional vibrations. Simple analytical approximations are derived for predicting the. Combining theoretical and experimental modal analyses on selfexcited vibration induced by dry friction between two elastic structures, we can explain the highorder sellexcited vibration phenomenon in which water droplets spurt from fourteen or twelve areas of the chinese culture relic dragon washbasin when it is rubbed with hands, and clarify the mechanism of the. There are two different types of chatter vibrations that can occur. Index termsself excited vibrations, dry friction, friction instability, limit cycle, stickslip. Self excited vibrations, dry friction, friction instability, limit cycle, stickslip. An experimental investigation was conducted in the laboratory with a pinondisk type sliding apparatus to study selfexcited vibrations induced. A nonlinear friction model for selfexcited vibrations. Prevention methods of selfexcited vibration due to dry. Self excited vibration of a flexibly supported shafting system in a gravity water tunnel was observed in the testing of friction of waterlubricated rubber bearings. Friction induced vibrations of a two degrees of freedom.
Conceptually, friction induced vibration can be accomplished only when forceoscillations are accompanied by motion oscillations along the direction of the force oscillations with a suitable relative phase. An experimental investigation was conducted in the laboratory with a pinondisk type sliding apparatus to study self excited vibrations induced by dry friction. Second is the presence of positive andor negative feedbacks that lead to dynamic destabilization and frictioninduced vibrations. Non smooth contact dynamics approach for mechanical systems. In numerical simulations, the linearised method of feedin energy, calculated purely based on friction work has provided some insights into the physical mechanism for instabilities. Hierarchical organization is the key feature of biological systems, which have capacity for selforganization, selfhealing, and selflubrication, so it is not surprising that hierarchy plays a central role also in. Effect of highfrequency excitation on friction induced. In order to obtain the mechanism of this phenomenon, a 7dof dynamic model of whole vehicle selfexcited vibration induced by the shimmy of front wheels which take the nonlinear factor of tire lateral force and the dry friction force in suspension. The vibrations induced by dry friction have been studied by jarvis and mills 4. Two different friction coefficients are used, and a normal force pressing the sliding body to a belt depending on an angle bar motion of the analyzed system is applied. Selfexcited vibration of whole vehicle with multiple. A harmonically excited dry friction oscillator is examined analytically and. The primer and of course the simplest work on dry friction is attributed to coulomb in 1785.
It is expected that these vibrations play a role in the behavior of sliding members with dry friction. The effect of dry friction stickslip coefficients and rubbing velocity on selfexcited vibration, and the limit cycle and hopf bifurcation solution of the system are obtained. The characteristics of these vibrations are devided into two groups by the type of friction. Several mechanisms have been proposed in the literature to explain frictioninduced vibrations. The excitation force in the self excited vibration maintaining the action is produced or monitored by the action itself, when the action retarding the excitation force vanishes. Then the vibration remains sustained at this value. Furthermore, the result of this study provides an understandable structure for vibroacoustical analysis of selfexcited vibrating systems. Chinese culture relic dragon washbasin is a selfexcited one induced by dry friction. We study rotational self excited vibrations of two frictionally coupled disks and consider the case of self excited vibrations arising in the presence of dry friction, where the disk relative velocity periodically changes sign passing through the point of discontinuity of the friction law. The nonlinear vibration theory and the experimental modal analysis are used in this paper to study the selfexcited vibration of the shellliquid coupled system induced by dry friction. Experimental investigation on the avoidance of self. Chinese culture relic dragon washbasin is a self excited one induced by dry friction. The characteristics of these vibrations are divided into two groups by the type of friction.
Stickslip vibrations, shooting method, dry friction, discontinuous systems. However, the dynamics due to friction induced instabilities is highly nonlinear and damping may offset some or all of the excess friction energy provided to the system. Self excited vibrations are observed in many technical applications. Prevention methods of selfexcited vibration due to dry friction of. Different types of vibrations induced by dry friction are investigated by means of a model apparatus described in part 1. Nonlinear behaviour of the friction coefficient results in self excited vibration and causes undesirable stickslip oscillations. Friction induced vibration in vehicle clutches and brakes, vehiclebridge interaction and flow induced vibration circular wood saws, cds, dvds, in machining, fluidconveying pipelines are examples of self excited vibration. Selfexcited vibration represents an important phenomenon in physical and mechanical systems. Under certain conditions, the steady state sliding motion becomes unstable. The presence of selfexcited vibrations itself can be highly detrimental to the performance of me. The intensity of self excited vibration is often so high that a save run is impossible and can result in a failure. A selfexcited friction pair is modeled by a mechanical system of two degreesoffreedom with a normal force varying during the block displacement.
Selfexcited vibrations caused by dry friction, which is generally expressed as a function of relative sliding velocities between two. Investigation of selfexcited vibrations in tread brake unit. The physical system, which we are concerned with, is a harmonically excited, dry friction oscillator fig. The contact elastic and dissipative characteristics are represented by equivalent stiffness and damping coefficient in the axial as well as torsional direction. This study deals with a forced self excited vibrating system accompanied by dry friction as an example of a nonlinear system with discontinuities. Timedependent static friction is studied as well as application in a system with 2dof. The appearance of self excited vibrations caused by dry friction of two elements or their contact surfaces is common practice in nature and technique. The instability leads to the occurrence of stable limitcycle type self excited vibrations. In selfsustained systems, these mechanisms fall into two distinct categories. Read statistics of complex eigenvalues in frictioninduced vibration, journal of sound and vibration on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Stick slip phenomenon arises due to alternating elastic and plastic deformation mech anisms in the contact zone. The vibration characteristics are changed when transition occurs from steady state friction. Friction induced oscillations result in deterioration of performance of disc brakes and are generally undesired. Frictioninduced oscillations of a nonasbestos organic pin. A dynamic lagrangian frequencytime method for the vibration of dryfrictiondamped systems.
Vibrational interaction of two rotors with friction coupling. Forced selfexcited vibration with dry friction applied nonlinear. It can have a strong impact on the numerical results and consequently on. A one degree of freedom nonlinear dynamics model of self excited vibration induced by dry friction is built firstly, the numerical method is taken to study the impacts of dynamics parameters on self excited vibration. International journal of mechanics instability induced by dry.
Vibrations are analyzed on indenter on disk system using brass and steel samples as. It is observed that the instability can be suppressed by the tangential highfrequency excitation only for a specific range of strength of excitation. The spectra of the oscillations are related to the modal frequencies. Dry frictioninduced selfexcited vibration between sealing disc and pipe is the source of chatter vibration on pig, and lead to the wear of pigs sealing disc in natural gas pipeline. Interaction between selfexcitation and parametric excitation. Introduction the presence of friction induced self sustained vibrations can be highly detrimental to the performance of mechanical systems.
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