Coupled Thermal-structural analysis in ANSYS Workbench

[davidfam]

Hi all,
I'm currently working on my bachelor's thesis in mechanical engineering. I must simulate a brake model, which consist of 1 rotor and 1 stator. The rotor rotate around z-axis and the stator move along z-axis. When pressure is on stator placed. The stator and rotor will be pressed together.

i used Coupled Thermal-structural analysis in ANSYS Workbench with solid226, but the result seemed to be not so good since the min Temperature, which appear on knots near max Temperatur of both rotor and stator is cooler than reference Temperatur (22°C) and the Total Deformation of rotor is relatively large.

I tried to reduce Net size and timestep but without success.
Is there something wrong with my simulation? Can someone please help me. Thank you and sorry for my bad in english

 

[Mech_Engineer]

What boundary conditions are you applying to the model to prevent rigid body motion?

 

[davidfam]

What boundary conditions are you applying to the model to prevent rigid body motion?

Thank you for your answer. Here is my boundary condition:

In my model, i define rotor is a Revolute joint, which can only rotate around z-axis (I'm a beginner so I really confuse hier because i don't know, if this definition can prevent rigid body motion of rotor or i must apply another boundary condition. Do you have any advice?)

And i set the surface, where pressure applied on stator as remote displacement with only z component free as below:

Thank you!

 

[davidfam]

Hi all,
i have solved the problems above but now i want to simulate a real model of aircraft multi discs brake with 6 stators and 5 rotors using coupled thermo-mechanic. It looks like:

Boundary conditions:
5 rotos move and rotate around z-axis
5 stators move only along z-axis
6th stator is fix
Pressure 1Mpa is applied on 1st stator
But the result is so strange due strange movement of the discs(rotors and stators) as the video below.


Can anyone pls help me. Thanks

 

[Mech_Engineer]

It seems as though the model is underconstrained; I'd recommend trying to solve using smaller time steps, and make sure your contact conditions have a reasonably-sized pinball region. A larger pinballl region might help with the problem you're seeing.

Some more reading here regarding contact conditions: http://www.padtinc.com/blog/the-focus/be-a-pinball-wizard-with-contact-regions-in-ansys-mechanical

 

[davidfam]

Thank you for your advice I think maybe my problem is the definition of contact body and contact target. I defined 1st stator as contact body and 1st rotor as contact targen in 1st contact but in 2nd contact i define 1st rotor as contact body and 2nd rotor as contact target (?) ... and so on for next rotors and rotors. I will try to change it and pinball region too as you advised and tell the result tomorrow ;)