Thermo-Mechanical Coupled Analysis
of an Automotive Disk Brake
In this example, we present a 3D transient dynamic analysis
of an automotive disk brake. The model has frictional contact,
large displacements and strong thermo-mechanical coupling. The
sources of thermo-mechanical coupling are the conductive heat
transfer between the rotor and pads which only occurs when there
is contact, the heat generation due to friction, and the stresses
caused by the non-uniform thermal expansion.
The brake geometry is shown in Figure 1 below. Note that a
simplified model of the brake disk/rotor is used in this simulation
where holes and slots are ignored.
Figure 1 Schematic of Brake
Unlike in most brake analyses, the rotor deceleration was not
prescribed in this model. Instead, the rotor was given an initial
angular velocity corresponding to a vehicle speed around 200
km/h, and was augmented with a concentrated mass at its center
to account for the vehicle's inertia. A strong braking force
was then applied to the brake pads and the rotor deceleration
was predicted from the numerical simulation.
The temperature distribution throughout the simulation is shown
in the animation above. Note that a non-uniform time scale was
used in the animation. Initially, very small steps were taken
due to the large angular velocity of the disk. The time steps
gradually increased as the disk slowed down. Finally, much larger
time steps were taken once the rotor stopped rotating (around
t = 4.75 s) to simulate the final brake cooling.
This solution illustrates one of the many complex industrial
problems involving frictional contact and thermo-mechanical coupling
that can be solved using ADINA.
Disk brake, thermo-mechanical coupling, thermal structural
coupling, friction, contact, brake simulation, transient dynamic