Acoustic radiation controls friction: Evidence from a spring-block experiment

TL;DR

This study provides experimental evidence that acoustic radiation influences frictional dynamics, demonstrating that damping feedback from acoustic waves can be modeled as a harmonic oscillator with radiation damping, affecting the noise spectrum.

Contribution

The paper introduces a simple harmonic oscillator model incorporating radiation damping to explain acoustic noise spectra in spring-block experiments, highlighting the role of acoustic feedback in friction.

Findings

Acoustic radiation affects the noise spectrum in sliding experiments.

A harmonic oscillator model with radiation damping accurately explains the observed spectra.

Experimental evidence supports the significance of acoustic feedback in friction dynamics.

Abstract

Brittle failures of materials and earthquakes generate acoustic/seismic waves which lead to radiation damping feedbacks that should be introduced in the dynamical equations of crack motion. We present direct experimental evidence of the importance of this feedback on the acoustic noise spectrum of well-controlled spring-block sliding experiments performed on a variety of smooth surfaces. The full noise spectrum is quantitatively explained by a simple noisy harmonic oscillator equation with a radiation damping force proportional to the derivative of the acceleration, added to a standard viscous term.