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[cmanjunath]

Hi Friends!

I am getting huge difference in contact forces between Bonded and frictional contact for same loads and BCs, pls see the pic below. Is that justifiable, let me know if any specific reason for that, or there may be an error in calculation.

[cmanjunath]

[Vigneswaran Sridharan]

Hey There is a difference between both these contacts in capturing the physical behavior correctly.
In the case of Bonded contact, the value of 'Normal force' (that prevents penetration between bodies) and 'Tangential force' (that prevents sliding between bodies) are high.
Whereas in Frictional contact, 'Normal force' could be zero when bodies separate out and the 'Tangential force' is a function of the normal force.
Some of the factors that influence contact forces between two bodies at the interface are:
Material of both bodies.
Shape and topology of both bodies.
Kinematics of interacting bodies.
I suggest you look into Contact Mechanics | Ansys Innovation Courses to understand the behavior and how to set up contacts.
Vigneswaran
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[peteroznewman]

Are the angles shown in the illustration accurate or are they exaggerated to make them easy to see?

[cmanjunath]

Yes, They differ by around 5 degrees, Picture shown is not the exact one, values are only similitudes.
Main point here is when i use bonded contact, horizontal component force reduces to very low value. against that of frictional contact.

[peteroznewman]

The bonded contact horizontal force component is simply the vertical force * sin(angle).
1000*sin(4.6) = 80 N.
The bonded contact vertical force component is simply half the total radial force.
The frictional contact horizontal force component is much higher because it is a sliding wedge instead of a bond. That creates a large mechanical advantage.

[cmanjunath]

Thanks a lot Peter!
Now i have more clarity.