GRID DEPENDENCY TEST ON BEVEL GEAR SIMULATION

1. GRID DEPENDENCY TEST:

• A smoother mesh provides smoother and more accurate results. The finer the mesh gets, the easier it gets in visualizing the contours. Mesh refinement increases the closeness of the values to the true values.
• Mesh refinement may increase the total number of nodes and elements in the mesh which actually increases the computation time.
• Therefore, it is necessary to find a suitable mesh size so that further refinement does not change the results significantly.
• In a Grid Dependency test, the analysis is completed for different mesh sizes starting from a higher value to lower values for element size such that after a particular point (element size), reducing the size and increasing the refinement does not affect the results significantly. From the obtained results, one mesh size is picked for further analysis so that the results are almost accurate and the computation time and cost are reduced.

2. GRID DEPENDENCY TEST ON BEVEL GEAR SIMULATION:

OBJECTIVE:

To perform a grid dependency test for the Bevel gear simulation for mesh sizes of 6,5 and 4 mm.

GIVEN MODEL OF BEVEL GEAR:

MODIFIED MODEL FOR THE ANALYSIS

ANALYSIS SETTINGS:

GRID DEPENDENCY TEST RESULT:

From the results, it is clear that the values of von mises stress are increased and then decreased but there is only a slight difference. The values of total deformation are the same with slight differences in the total deformation average. Similarly, the equivalent elastic strain is also showing close results.

The mesh size of 6mm took the lowest computation time and was able to provide satisfactory results compared to other mesh sizes. Still, mesh size of 5mm has higher values for equivalent elastic strain and von mises stress. The computation time is almost equal for mesh size 6mm and 5mm(little more than 6mm).

Actually, a smoother mesh provides smoother and more accurate values. The finer the mesh gets , the easier it gets in visualizing the contours. Mesh refinement increases the closeness of the values to the true values. Hence, in this case, 4mm element size will provide smoother and more accurate results which increased computation time.

Therefore, a mesh size of 5mm is recommended from the grid dependency test.

3. SOLVING FOR VON MISES STRESS, TOTAL DEFORMATION AND EQUIVALENT ELASTIC STRAIN:

CASE 1: ELEMENT SIZE IS 6 mm

• Meshing:
• Element Quality:
• Total deformation:
• Von Mises Stress:
• Equivalent Elastic Strain:

CASE 2: ELEMENT SIZE IS 5 mm

• Element Quality:
• Total deformation:
• Von Mises Stress:
• Equivalent Elastic Strain:

CASE 3: ELEMENT SIZE IS 4 mm

• Element Quality:
• Total deformation:
• Von Mises Stress:
• Equivalent Elastic Strain:

CONCLUSION:

The total deformation is the same for all three cases but there are slight differences in the values of equivalent elastic strain and von mises stress.

The computation time increases as mesh refinement increases with the decrease in the element size.

The values of total deformation are the same with slight differences in the total deformation average. Similarly, the equivalent elastic strain is also showing close results. In this case, 4mm element size will provide smoother and more accurate results which increase computation time. The mesh size of 6mm took the lowest computation time and was able to provide satisfactory results compared to other mesh sizes. Still, mesh size of 5mm has higher values for equivalent elastic strain and von mises stress. The computation time is almost equal for mesh size 6mm and 5mm(little more than 6mm).

Therefore, a mesh size of 5mm is recommended from the grid dependency test.

The grid dependency test in this analysis was used to check how the result changes with the element size and a suitable element size of 5 mm are recommended for further analysis to reduce the computation time and cost without compromising the accuracy of the result.