Week 2 Bevel Gear Challenge

Objective: Static structural analysis for a bevel gear using three different mesh size. Compare results obtained from the analysis.

Size of mesh being used are 6mm,5mm and 4mm

Solution:

Grid Dependency: Grid dependency test is the term used to describe the improvements of results by using successively smaller cell sizes for the calculations. The solution get more accurate as the mesh becomes finer. The normal FEA technique is to start with a course mesh and gradually refine it until the changes observed in the results are smaller than a predefined acceptable error.

Procedure:

-Firstly, open static structural in ANSYS workbench.

-There is no material specified, hence we are going with the manual material i.e Structural Steel.

-Now, we import the bevel gear geometry to ANSYS workbench and oipen the imported geometry in spaceclaim.

-We make our required changes to the geometry in spaceclaim and open the geometry in mechanical module.

-Now, we give the connections to the geometry where the connections take place when they go through the simulation.

-After giving the connections we assign joints to the gears by selecting inner face of the geometry and convert them to revolute joints.

-Now, for meshing the geometry we assign the sizing as 6mm based on case1.

-We provide the boundary conditions through analysis settings.

-Assigning the two joint loads to the gears by one gear will rotate for six steps where one step rotates 20 degrees and so on where the other gear will rotate in opposite direction with moment of 10N.

-Now, we run this simulation for Von-Mises stress, Equivalent elastic strain and Total deformation. So, we provide all the three required solutions and run the simulation.

Case-1: mesh of 6mm

Equivalent Stress:

Equivalent Elastic Strain:

Total Deformation:

Case-2: Mesh of 5mm

Equivalent Stress:

Equivalent Elastic Strain:

Total Deformation:

Comparision:

Mesh Size Equivalent Stress(MPa) Equivalent Elastic Strain(mm/mm) Total Deformation(mm)

64.511

5mm 592.37 0.0032888 64.511

4mm 713.9 0.0037616 64.511

Conclusion:

-From the table above and from the simulations we can say that the Total deformation for the bevel gear is constant.

-From the tabel we can say that the difference between the Equivalent stress of 6mm mesh and 4mm mesh is so close when compared to that of Equivalent stress of 5mm mesh.

-The run time for all the three mesh sizes were almost the same.

-When compared with Equivalent Elastic Strain 6mm and 4mm are almost equal.

-Hence, I would recommend 5mm mesh as the optimum mesh for the bevel gear simulation.