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The Oscillations of a Mass-Spring System with Multi-Step Friction Damping

Published online by Cambridge University Press:  26 October 2023

J P Jones
J P Jones*
Affiliation:
Department of Aeronautical Engineering, University of Southampton
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Summary

An analysis is made of the free and forced oscillations of a single degree of freedom system damped by a multi-step friction damper It is shown that in free oscillation the decay is similar to that obtained with viscous damping, but in this case the frequency increases as the friction increases

In forced oscillation the exact solution is little different from that obtained using an equivalent viscous damper if the ratio (natural frequency/forcing frequency) is less than 1 37 For higher values the mass will remain at rest during some part of the cycle if the friction is large enough, when the above ratio is 3, 5, 7, etc, “stops” occur, however small the friction The variation of phase angle is unusual, under certain conditions the displacement leads the exciting force

On the basis of the results a criterion for the use of the equivalent viscous damper in ground resonance calculations is suggested

Type
Research Article
Information
The Journal of the Helicopter Association of Great Britain , Volume 13 , Issue 1 , February 1959 , pp. 57 - 69
Copyright
Copyright © Royal Aeronautical Society 1959

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References

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