Effect «the energy transfer» in ropes of two-end lifting

Abstract

The analysis of the literature on the study to identify the effect of "energy transfer" in the
ropes of drum lifting equipment. The determination of transient dynamic processes in the elastic
connections of a lifting installation for a three-wheeler torsion system at moments of elastic forces
is an important aspect for finding the strength characteristics of the ropes.
An equivalent torsional dynamic scheme of a two-end lift with discrete masses and elastic
connections is given to consider the dynamic processes in its cable course and reveal the effect of
“energy transfer”. The masses of the ropes are given to discrete masses of the lifting installation
according to the method of Timoshenko-Kozhevnikov. Analytical expressions are obtained in the
moments of elastic forces for a double-end drum lifting installation when a pulse is received by one
vessel from the barrel reinforcement when the end loads move in the shaft.
The numerical results of solving differential equations are presented in the form of
oscillograms, from which it can be seen that in one cable the moment of elastic force of the lifting
installation changes according to the law of the product of sines, and in the other cable - according
to the law of the product of cosines. This phenomenon is called a beat or "energy transfer."
The results of solving differential equations are presented in the form of oscillograms. It was
determined that when the distribution coefficients y1 and y2 are equal to or almost equal to one, the
effect of “energy transfer” occurs between the elastic links of the three-mass mechanical system of
a two-end lifting installation and the amplitude of rope oscillations changes from zero to a constant
value given by the initial conditions. For the equality of the unit of the distribution coefficients of
the three-mass system, it is necessary to perform the equality of the moments of inertia of the
extreme discrete masses and stiffnesses of the elastic links.