Learning Forum

[Juli]

Hello,

for the assessment in our Finite Elements course, we need to perform an analysis of an elevator torque arm (Cessna 182) in Ansys APDL with the following description:

"It had been hypothesised that a good approximation of a bearing load can be created using a Pressure - on Lines type loading. You have been tasked to check and see if this is the case and hence prove or disprove the hypothesis. To make the process as efficient as possible, the geometry shown below should be used to test the hypothesis"

[peteroznewman]

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Juli

Your drawing looks like an incomplete part. Here is a more realistic part.

For this exercise, you might hold the 25 mm edge fixed and apply the force to the ID of the hole. But you should probably check that with the professor.

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[Juli]

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peteroznewman

Thanks for your quick response.

Would you apply the force as in the picture below? In all directions?

Thanks in advance

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[peteroznewman]

Array
A link generally can only push and pull on a pin, so the net force should be in the Y direction. However a pin in a hole can only push on the side of the hole (not pull) so I would only put the force on one half of the circle.
One way to distribute the force around the half circle is to have a cosine fall-off. That means that for the node at top-center, the factor is 1.0 while for the nodes on either side of center, the factor reduces to 0.0 at 90 degrees from top-center where the factor is the cosine of the angle from top-center. Since the assignment is to study "Pressure on lines" loading, pressure is always normal to the surface. So the Y component of all the normal forces around the half circle must add up to 740 N.
The most accurate way to calculate stresses in a link created by a pin pushing on the side of a hole is to model the pin in the hole and apply frictional contact. Representing the contact forces by a cosine fall-off of pressure is a reasonable approximation.

[Juli]

Array
Thank you Sir, i will try this.

[devam_18]

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Juli Can you please share the solution or screenshots for this problem as i am not able to create this geometry please help

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