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1.3 INTRODUCTION TO TYPES OF CONDUCTOR MOTION
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Аннотация
For the purposes of this book, wind-induced conductor motion
is considered to include those types of repetitive or cyclic
motion which derive their energy from wind forces applied to
conductors.
Energy absorbed by the conductor may be dissipated by internal
friction at the molecular level; by inter-strand friction;
by transference to clamps, dampers, spacers, and suspension
assemblies; by transference to adjoining wires (in the case of
bundled conductors); or by return of energy to the wind.
The relative magnitudes of these dissipations, and their
phase positions within each motion cycle, determine whether
the conductor motion will be suppressed, sustained, or accelerated.
Three different categories of cyclic conductor motion are
recognized. These are aeolian vibration, conductor gallop,
·tl wake-induced oscillation. They are distinguished from
_ ... ch other by different mechanisms of energy transfer, by different
motion patterns, by vastly different frequencies and
amplitudes of vibration, and by different effects upon conductors,
clamps, and other equipment.
