## General Mechanical

#### Transient Structural: Flipping the contact/target faces of a frictional contact changes the results

• Nikke
Subscriber

Hi,

I'm running a pendulum analysis (Structural Dynamics course in Ansys Innovation Courses).

The goal is to study the motion of the pendulum while a frictional contact is causing damping to the motion of the pendulum. However, I noticed that flipping the contact and target faces affects to the results quite a lot.

Model:

-Remote Displacement fixes all 6 DOF of the face of the pin.

-Gravity applied to the Global +Z direction.

-The frictional contact has been defined between the pin and the pendulum. The coefficient of friction is 0.1.

• John Doyle
Ansys Employee
The contact region properties (i.e. penetration tolerance, normal and tangential stiffness, pinball...etc) are all derived based on underlying elements (size and stiffness) beneath the contact elements. The target elements just serve to define a mathematical boundary that the contacts need to respect. If the mesh pattern is different between the two bodies, these properties might be different enough to influence the results. You could try to refine mesh until results converge to same answer. You could also force the contact properties to be same (in contact region details window) and turn off stiffness updating scheme to eliminate that variable as well.n
• Nikke
Subscriber
Thank you Array,I did the mesh refinement and the results match each other now way better. Thank you also for the advice with contact settings.n