The Intrinsic Variables affecting the Stick-Slip Process

Rabinowicz, E.

doi:10.1088/0370-1328/71/4/316

Cited by 303 publications

(138 citation statements)

References 9 publications

Supporting

Mentioning

125

Contrasting

Unclassified

Order By: Relevance

“…since the cosine transform vanishes as (3-co) condition for equation (IS) to have a solution with {J ¢ 0 is that fa h (t)dt> f, which is the second inequality of (9). Thus, if the decay process is monotonic,…”

Section: F-h(o)=f-l;h(t)dtmentioning

confidence: 97%

Stability of Steady Frictional Slipping

Rice

Ruina

1983

Journal of Applied Mechanics

991

813

View full text Add to dashboard Cite

show abstract

Section: F-h(o)=f-l;h(t)dtmentioning

confidence: 97%

Stability of Steady Frictional Slipping

Rice

Ruina

1983

Journal of Applied Mechanics

991

813

View full text Add to dashboard Cite

show abstract

“…This way avalanche like strand movements might be triggered which could release enough frictional heat beyond the stability margin of the cable [5,7]. However, any realistic friction event, including stick-slip, is associated with minimal relative movements on the order of several µm which is the size of the surface asperities of the contact [10,11]. Therefore, sliding amplitudes smaller than say 1 µm are considered irrelevant.…”

Section: Relevant Amplitudes and Frequenciesmentioning

confidence: 99%

Dynamic response analysis of superconducting coils in Wendelstein 7-X and mechanical quench test

Fellinger

Freundt

Hathiramani

et al. 2011

Fusion Engineering and Design

View full text Add to dashboard Cite

The Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-PlanckInstitut für Plasmaphysik in Greifswald, Germany. The W7 X magnet system contains 70 superconducting (sc) coils which are supported by a massive central steel ring structure via bolted connections and by numerous welded as well as gliding inter-coil elements. Load tests on prototypes of bolted coil to support ring connections whose flanges partially open during high field operation, and of sliding support structures between the coils showed that stick-slip events at their contact surfaces cause shock waves. In order to assess the risk of a shock-induced quench of the superconductor, one of the coils was subjected to impact loads -the so called mechanical quench (MQ) test -in the course of the cryogenic acceptance tests at CEA in Saclay, France. No quench could be triggered even with the lowest coil stability margin. The paper demonstrates that the amplitudes of the shock waves in the W7-X magnet system are comparable to those generated by the impacts in the MQ tests. For that purpose, finite element (FE) models of both W7-X and the MQ test simulating the dynamic responses were developed and successfully validated against measurements. The Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-Planck-Institut für Plasmaphysik in Greifswald, Germany. The W7-X magnet system contains 70 superconducting (sc) coils which are supported by a massive central steel ring structure via bolted connections and by numerous welded as well as gliding inter-coil elements.Load tests on prototypes of bolted coil to support ring connections whose flanges partially open during high field operation, and of sliding support structures between the coils showed that stick-slip events at their contact surfaces cause shock waves. In order to assess the risk of a shock-induced quench of the superconductor, one of the coils was subjected to impact loads -the so called mechanical quench (MQ) test -in the course of the cryogenic acceptance tests at CEA in Saclay, France. No quench could be triggered even with the lowest coil stability margin.The paper demonstrates that the amplitudes of the shock waves in the W7-X magnet system are comparable to those generated by the impacts in the MQ tests. For that purpose, finite element (FE) models of both W7-X and the MQ test simulating the dynamic responses were developed and successfully validated against measurements.

show abstract

“…The detailed facts such as the time-dependent increase of static friction during stationary contact [Dokos, 1946;Dieterich, 1972], the continuous reduction of friction from static friction to dynamic friction with ongoing slip displacement [Rabinowicz, 1951 ], the velocity dependence (particularly velocity weakening) of steady state friction, and the continuous change of friction with slip when velocity is changed, all had been discovered and incorporated in the friction law [e.g., Dieterich, 1978] before the work by Dieterich [1979]. Even the concept of memory of the interface, which would be generalized as state variable later [Ruina, 1983], had already been recognized [Rabinowicz, 1958] by then. However, they were all about how and why friction, in the sense of threshold strength, changes.…”

Section: Introductionmentioning

confidence: 99%

Conceptual and physical clarification of rate and state friction: Frictional sliding as a thermally activated rheology

Nakatani¹

2001

J. Geophys. Res.

330

391

View full text Add to dashboard Cite

Abstract. We observed slow frictional slip occurring at a constant shear stress below the nominal friction level and compared it with the time-dependent strengthening of the frictional interface, which was also tracked experimentally. It was found that slip velocity decreases as the interface strengthens duc to aging, whil'• it increases with the applied shear stress. These dependencies wcrc both exponential and were of similar magnitudes, as implied by the framework law of rate-and state-dependent friction. In the spirit of the adhesion theory of friction the dependence of slip velocity on interface strength is understood to be the result of the change of the shear stress acting on frictional junctions duc to the change of junction population, though the observed dependence was somewhat stronger than a simple model based on this idea predicts. By correcting the observed slip velocity for the effect of the change of the interface strength, wc could obtain a unique relationship between stress and slip velocity, which may bc readily compared with a standard theological formulation. Thus the obtained relationship between stress and slip velocity showed a reasonable agreement with the absolute rate theory over a temperature range of 25-800øC for the present experimental condition (fmc albitc powder, 20 MPa normal stress, no pore water).

show abstract

The Intrinsic Variables affecting the Stick-Slip Process

Cited by 303 publications

References 9 publications

Stability of Steady Frictional Slipping

Stability of Steady Frictional Slipping

Dynamic response analysis of superconducting coils in Wendelstein 7-X and mechanical quench test

Conceptual and physical clarification of rate and state friction: Frictional sliding as a thermally activated rheology

Contact Info

Product

Resources

About