NON-LINEAR STATIC STRUCTURAL ANALYSIS:

PHYSICS OF THE PROBLEM

In this process, the wire is bent by the force applied on it due to the rotation of lever.

a.Bending wheel is fixed.

b.Lever is given a rotational motion.

Due to the above motion, the wire is deformed and it will follow the path of the wheel and bends.

NON-LINEAR MATERIAL PROPERTY:

The wire is bent above its yield strength to get a permanent deformation. Hence, we go for Nonlinear analysis by providing the Non-linear material property of copper.

ANALYSIS IN STEPS

Since, deformation force applied on wire is so high we have to apply it step by step but not directly

MODEL:

The model consist of 3 parts :

1. Bending wheel

2. Bending lever

3. Wire

CO-ORDINATE SYSTEMS:

In this simulation, 2 different co-ordinate systems are used:

1.Global coordinate system - Which is provided by default.

2.Reference coordinate system – This is provided inorder to get a refined mesh in the region of sphere influence with respect to the reference co-ordinate.

CONTACTS:

In this simulation there are in total three bodies:

However, only two of those is required to be defined properly for the simulation.

1.Contact between wire & wheel – Frictional

2.Contact between wire & lever – Frictional

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Contact Settings :

a.Co-efficient of friction – 0.2

b.Formulation – Augmented LaGrange.

c.Normal Stiffness – Factor

d.Normal Stiffness' factor – 0.1

e.Upgrade Stiffness – Each Iteration

f.Interference Treatment – Add offset & Ramped effects.

JOINTS :

A Revolute joint is provided at the lever as it can be provided with the angular deformation in degree using the joint loads.

JOINT SETTINGS :

A.Connection type -Body to ground reference is given.

B.Behavior – Rigid

MESH:

a.Tetrahedral mesh of 8mm is provided in all other body.

b.However in the lever protruding surface refined mesh of 2mm is provided.

c.In the contact between, wire and wheel, there is a mesh of size 0.8 mm – This is done by using the sphere of influence and local coordinate system generation.

ANALYSIS SETTINGS:

NUMBER OF STEPS:

This is the load application steps. So here a total deformation of 140 Deg angle is provided in 8 steps .

MAXIMUM SUBSTEPS:

Initially, the max substep was set at 10. So, there was a FSUM error.

Hence, later it is adjusted to 25, then the solution was solved.

Physically, It means that if the solution is not converged in 25 iteration, then abort the operation

SUPPORTS:

FIXED SUPPORT:

1.Wheel is provided with the fixed support

2.The end face of the wire is also fixed as the initial simulation did not converge, when the end surface was not fixed as result the wire was slipping out.

JOINT LOAD :

The revolute joint is provided with the rotation at different angle step by step.

However, the coordinate axes is to be adjusted as such that the rotation is taking the clockwise direction.

POST PROCESSING :

1. Factor of Safety-

Using the isocap tools which will help to isolate the regions in which the factor of the safety compared to maximum ultimate strength

MINIMUM FOS:

MAGNESIUM ALLOY	ALLUMINIUM ALLOY	COPPER ALLOY
0.40216	0.58296	0.41271
0.40221	0.58657	0.41378
0.40303	0.58746	0.41441
0.40327	0.58799	0.41587

EQUIVALENT STRESS:

Srno	Material	Von-misses stress (Max)
		Mpa
1	Copper Alloy	344.43
2	Aluminium Alloy	336.13
3	Magnesium Alloy	261.16

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