Ansys Learning Forum Forums Discuss Simulation General Mechanical Coupled field transient of brakedrum Reply To: Coupled field transient of brakedrum

peteroznewman
Subscriber

Hello Rohan,

You would think you could just type in 36 rad/s as an initial condition for the rotational velocity at t=0 within Mechanical.  I have done that with other software.

You can do that using an APDL Command Object. Use the command ICROTATE to apply OMEGA to a list of nodes on the disc and provide two points to define the rotation axis.

If you want to avoid using APDL, then you need to use a multistep approach. A more efficient set of steps than the one in my previous reply requires turning Time Integration Off and On.

  • Step 1, turn off Time Integration, use a Joint Displacement of 0.0036 radians and an end time of 0.0001 seconds. That creates a 36 rad/s rotational velocity.  Since Time Integration is off, this massive acceleration causes no stress.
  • Step 2, Deactivate the Joint Load so the revolute can spin freely, turn on Time Integration so the brakes can be applied in the next step, use an End Time of 0.0002 seconds.
  • Step 3, Ramp up the Brake force with an end time of 0.1 s
  • Step 4, Keep the Brake force Constant with an end time of 1 s.  The disc will stop somewhere between t=0 and t=1.

Check the rotational velocity to make sure the model attained the desired rotational velocity.