Wire Bending Simulation using ANSYS Workbench

OBJECTIVE:

Wire bending has to be performed for 3 different materials using ANSYS Workbench. For the following case, case setup and comparison of results should be done.

To simulate using three different materials for wire namely Aluminum alloy (Non-Linear), Copper Alloy NL, and Magnesium Alloy NL, and to compare results of equivalent stress and, equivalent elastic strain for the wire.

PROCEDURE FOR CASE SETUP:

1. Open ANSYS >> Drag and drop static structural in the project schematic window.

2. Go to engineering data for defining the materials given in the problem. Choose aluminum alloy NL, copper alloy NL, and Magnesium alloy NL from the material library. This is shown in the figure below.

For the first simulation, the material chosen is aluminum alloy NL.

3. Select the model tab to establish the meshing, contact definitions, and analysis settings definition. Rename the parts according to convenience.

4. Go to contact and define the contacts shown in the figure below. The first contact establishes the contact between the wire and the lever. The second contact establishes the contact between wheel and wire. The frictional coefficient is 0.2.

5. For meshing, tetrahedrons are used for the entire model by using the patch conforming method. Face sizing option is used where the contact between wire with lever and wheel is present. The element size is shown in the figure below. 

For the above-shown faces, an element size of 2.2 mm is used.

For the above-shown region, the type used is a sphere of influence. This is defined by creating a coordinate system near the interface between wire and wheel. The sphere radius is 7 mm and the element size is 0.8 mm.

The final meshed model is shown in the figure below.                

6. Go to analysis settings. The number of steps defined for this analysis is 8. For the first time step, the case setup is shown in the figure below.

For the time steps 2-8, the definition is shown in the figure below.

7. For the boundary conditions, a revolute joint is defined for the lever to rotate. The rotation is defined using the tabular values. This is shown in the figure below.

8. The end face of the wire is fixed to arrest the motion. Fixed support is defined for the wheel so that it does not rotate when a rotation is given to the lever.

9. The output requests for equivalent stress and equivalent elastic strain are placed. It is to be noted that the output requests remain the same for all three cases.

10. From the analysis settings, hit on solve to start the simulation.

12. The rest of the simulation cases has to be done by changing the materials of the wire. 

 GRAPHS AND CHARTS OBTAINED:

1. The equivalent stress and elastic strain obtained for aluminum alloy are shown in the figures below.

2. The equivalent stress and elastic strain obtained for copper alloy are shown in the figures below.

3. The equivalent stress and elastic strain obtained for magnesium alloy are shown in the figures below.

RESULTS AND DISCUSSION:

Case 1:

1. The equivalent stress observed in the wire for all the materials is shown below.

2. The equivalent elastic strain observed in the wire for all the materials is shown below.

3. The animation files for the equivalent stress is shown below.

4. The animation files for the equivalent strain are shown below.

COMPARISON OF RESULTS:

For the comparison of the results, the maximum values of all the output requests are taken for convenience.

From the above table, it can be inferred that the maximum equivalent stress is generated in copper alloy with a value of 650.05 MPa. The least equivalent stress is obtained in magnesium alloy with a value of 268.05 MPa.

The strain is almost the same for copper alloy and magnesium alloy with a maximum value of 0.0059. The maximum value of strain is observed in aluminum alloy with a value of 0.00635.

CONCLUSION:

 From the animation it can be seen, the maximum strain of the wire is observed near the corner of the wire slot of the wheel. The remaining portion of the wire does not undergo that much plastic deformation compared to the former region.

Stiffness is the extent to which an object resists deformation in response to an applied force. Material with a higher elastic modulus has a higher stiffness value. This is the reason for the higher level of stress is experienced in the case of copper alloy.

From the table, it can be seen that magnesium alloy wire can be chosen since it has a lower elastic modulus therefore it is more flexible compared to the other two. Moreover, other factors like cross-sectional area and length of specimen affect the stiffness of the material. But in this challenge, since the cross-section and length are fixed, the major criteria for concern are the equivalent stress and equivalent strain value.

However, according to the type of application the material must be selected. For example, aluminum and copper wire must be selected when the type of application is wires. Hence, from these simulation results, it can be inferred that magnesium alloy can be easily bent into wires followed by aluminum alloy and copper alloy.

Drive Link: https://drive.google.com/file/d/1T6WCFBYhh4h_H4RjM_DLeekIaLxgnt24/view?usp=sharing