Universal Joint simulation using ANSYS Workbench
OBJECTIVE:
To perform transient structural simulation on a double universal joint with a spring using ANSYS Workbench. The following objectives have to be satisfied.
Case 1: For the joint with springs the material structural steel has to be used
Case 2: For the joint with springs the material stainless steel has to be used
Case 3: For the joint with springs the material titanium alloy has to be used
PROCEDURE FOR CASE SETUP:
1. Open ANSYS >> Drag and drop the Transient Structural module in the project schematic window.
2. Go to engineering data for defining the materials given in the problem. Select the following materials from the materials library.
3. Select the model tab to establish the meshing, joints, and analysis settings definition. Assign the material structural steel to the joint with the spring.
4. Delete all the default contact definitions in the contacts tab. The joint definitions are shown in the figure below.
A fixed joint is defined at the end of the spring.
Two body-ground revolute joints are defined for the two joints. It is to be ensured that the axis of rotation is proper with the given axis.
A body-body revolute joint is defined between the two joints. It is shown in the figure below.
5. For meshing, face sizing is used in the regions given below. An element size of 2 mm is used in these regions.
The final meshed model is shown in the figure below.
The element metrics are shown in the figure below.
6. Go to analysis settings. The number of steps defined for this analysis is 5. For all the time steps, the definition is shown in the figure below.
7. The boundary conditions are shown below. The joint load is defined in the revolute joint.
8. The output requests for equivalent stress and total deformation are placed.
9. From the analysis settings, hit on solve to start the simulation. Similarly, by changing the material of the joint with spring all other case setup is done.
RESULTS AND DISCUSSION:
1. The total deformation obtained for all three cases are shown below.
2. The equivalent stress obtained for different materials are shown below.
3. The total deformation obtained on the universal joint with spring is shown below.
4. The equivalent stress obtained on the universal joint with spring is shown below.
ANIMATION FILES:
1. The equivalent stress animation for different materials are shown in the figure below.
2. The total deformation animation for different materials are shown in the figure below.
CONCLUSION:
From the simulation, it can be seen that for both cases the solution converged without any errors.
The output parameters are tabulated below.
| Material for the universal joint with springs | Total Deformation (in mm) | Equivalent Stress (in MPa) | Total Deformation in universal joint with springs (in mm) |
| Structural Steel | 38.637 | 1851.8 | 23.858 |
| Stainless Steel | 38.637 | 1791.5 | 23.858 |
| Titanium alloy | 38.637 | 908.44 | 23.858 |
From the above table, it can be seen that the total deformation remains the same for all three cases with a value of 38.637 mm.
The equivalent stress observed is highest for structural steel with a value of 1851.8 MPa. The equivalent stress is least for titanium alloy with a value of 908.44 MPa. The value obtained for stainless steel is 1791.5 MPa. Structural steel has higher equivalent stress because it has a higher young's modulus. Since the stress value is directly proportional to young's modulus it has the highest equivalent stress.
Therefore, it can be concluded that the maximum equivalent stress for structural steel is the highest. The total deformation remains the same for all three cases. Hence, all the objectives are satisfied.