EXPERIMENTAL ANALYSIS OF TORSIONAL DEFLECTION AND ROTATION IN MECHANICAL SHAFTS

The presented article discusses the issue of
experimentally determining the angle of rotation in
structural elements subject to torsion. There are analytical
expressions for the theoretical calculation of the angle of
rotation of structural elements subject to torsion
deformation. This is solved on the basis of the well-known
Saint-Venant principle. Structural elements subject to
torsion deformation are called shafts, and if the crosssection
of this shaft is whole (this area is simply
connected), then the torsion angle is calculated using
methods the strong of materials. If there are holes along
the shaft axis (parallel to its axis), the shaft cross-section
will be a multiconnected area, then the issue of shaft
torsion is solved analytically using the theory of functions
of complex variables. Because the solution of the problem
boils down to solving the Laplace equation under
Neumann boundary conditions. Experimentally, the
solution is carried out by the photoelasticity method. For
simplicity, cylindrical shafts with rounded cross-section
are considered in this article. All the experiments carried
out were carried out within the elasticity limits of the
material of the selected samples (the elasticity limits of
different materials are different). However, sometimes due
to the influence of various technological factors, a large
difference arises between theoretical calculations and
practical calculations. For structural elements exposed to
torque, it is important to accurately determine the torsion
angle. In this paper, the dependence of the angle of rotation
in torsion on the amount of torque is experimentally
investigated. The experiments were carried out according
to two variants. The same amount of load ( p = 1 kg ) was
applied to samples of constant diameter and different
lengths made of aluminum material as test samples.
According to the values obtained through these
experiments, the change in the angle of rotation depending
on the length of the axis was studied. In the second series
of experiments, different amounts of loads
(m = 0.5, 1, 1.5, 2 kg) were applied to axes of the same
length ( L = 440mm ) and constant diameter (d = 10mm).
Based on the results obtained, the change in deformation
(proportional to the torsion angle) depending on the
applied load was analyzed. The obtained results were
displayed through graphs and histograms.