Figure 29. It is noted that the increase in the value
of pressure also has a role on the elastic behavior of
the couple disc / pads since the equivalent
stresses of Von Mises increases with the pressure
exerted.
Figure 29. Von Mises equivalent stress as a function
of the pressure applied to the brake pads.
3. General conclusion
1. The numerical analysis of the transient
thermoelastic behavior of the dry sliding contacts of
the disc-wafer pair was carried out using the
ANSYS 14.5 calculation code based on the finite
element method. We have been able to show the
influence of the position of the brake pads on the
disc and of certain significant braking parameters
such as the coefficient of friction, the choice of
material and the initial speed of rotation of the disc,
the pressure applied to the pads. Brake pressure, and
thermal conditions (disc temperature, heat flow
through the disc and heat exchange by convection
over the entire surface of the disc). The stresses and
strains of each configuration of the disc-pad couple
are expressed as a function of the braking time.
2. The comparative study of the four variants of
the disc-pad pair shows that the maximum stresses
are concentrated at the level of the grooved surface
of the disk (contact zone between the pad and the
disk), then they decrease in the direction of the base
of the bowl of the disk, and ventilation fins. The
pads located at the top and bottom of the disc give
greater stresses than those of the pads
placed to the right and left of the disc; this is due to
the position of the groove.
3. Numerical analysis of the thermoelastic
behavior of dry sliding contacts shows that the
coefficient of friction has a low influence on the
equivalent stress of a disc regardless of the braking
time. The equivalent stress decreases with the
increase in the coefficient of friction.
4. The results show that the stress field and the
strain field depend not only on the coefficient of
friction, but on other parameters such as; the initial
speed of rotation, the type of loading applied to the
pads (the pressure), the temperature of the disc, the
choice of the material of the disc as well as the
variation of the braking time.
5. The equivalent stress in the contact area
increases with increasing initial rotational speed of
the disc. The maximum equivalent stress that a
stainless steel disc can withstand is higher than that
of gray cast iron. Despite the fragility of gray cast
iron, the latter has a technological advantage such as
good resistance to corrosion and hot deformation.
6. The influence of the pressure also has a role on
the thermoelastic behavior of the dry sliding contact
between the disc and the pads.
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WSEAS TRANSACTIONS on APPLIED and THEORETICAL MECHANICS
DOI: 10.37394/232011.2022.17.26
S. Kerrouz, T. Tamine, M. Bouchetara