Structural Analysis with Grid Dependency Test on Bevel Gear using ANSYS WORKBENCH
Objective: Perform Grid dependency test for Bevel gear simulation using mesh sizes of 6, 5, 4 mm
Grid dependency Test: It can also be known as Mesh convergence Test. While performing Finite Element Analysis we are basically dividing a problem into finite number of elements to and perform meshing and other process on it to achieve accurate results. But this accuracy of results mostly depends on mesh element size. The bigger the size of mesh, the coarser it will be and lesser time it will take and hence inaccurate result may be obtained. The smaller the mesh size , the finer it will be and accuracte result will be obtained but it will take large computational time.
Their is always a point to have an accurate result by refining the mesh, and further refined mesh wont affect the characteristics or factors such as Equivalence stress significantly. This point is known as Grid dependency test which means analysis starts with coarser mesh, but as soon as mesh is refined the results dont get affected too much and depends on grid size. The main aim of this test is to give accurate result which mesh which is neither coarse nor finer which means almost an accurate result can be obtain with less computational time.
Geometry:
Contacts:
Frictional contact with symmetric behaviour , Formulational as Augumented langrange and Interface set as Adjust to touch.
Joints For Bigger and Smaller bevel gear:
Analysis Settings:
Joints with Rotation and Moment:
Moment of 100 N-mm with Rotation of 20 degree at each substeps was given.
Case 1: Bevel Gear 6 mm
Total Deformation:
Min.= 0.43 mm , Max.= 47.87 mm
Equivalence Stress:
Min.= 1.43xE-8 MPa, Max.= 5.41 MPa.
Equivalence Strain:
Min.= 1.35xE-13 MPa , Max.= 3.31xE-5 MPa
Case 2: Bevel Gear 5 mm
Total Deformation:
Min.= 0.43 mm , Max.= 47.87 mm
Equivalence Stress:
Min.= 1.44xE-8 MPa, Max.= 5.55 MPa.
Equivalence Strain:
Min.= 1.42xE-13 MPa , Max.= 3.60xE-5 MPa
Case 3: Bevel Gear 4 mm
Total Deformation:
Min.= 0.43 mm , Max.= 47.87 mm
Equivalence Stress:
Min.= 1.54xE-8 MPa, Max.= 5.45 MPa.
Equivalence Strain:
Min.= 1.30xE-13 MPa , Max.= 3.48xE-5 MPa
Conclusion:
Below is the table of different mesh size of Bevel gear with its solution in terms of Total deformation , Equivalence stress , Equivalence strain :
|
Bevel gear Size |
Deformation MM |
Equivalence stress MPA |
Equivalence strain |
|||
|
MM |
Min |
Max |
Min |
Max |
Min |
Max |
|
6 |
0.43 |
47.87 |
1.43*10-8 |
5.41 |
1.35*E-13 |
3.31*E-5 |
|
5 |
0.43 |
47.87 |
1.44*10-8 |
5.55 |
1.42*E-13 |
3.60*E-5 |
|
4 |
0.43 |
47.87 |
1.54*10-8 |
5.45 |
1.30*E-13 |
3.48*E-5 |
After comparing all the results of different mesh size of bevel gear , we have observed that there is not much change in values of deformaton, stress, strain and are almost similar. Further refining the mesh would give almost same result as previous mesh size and it will just increase computational time.
So we can conclude that Grid Dependency Test is achieved as results are almost similar.