Week 1 Stress Concentration on a Plate with hole

ANALYSIS OF STRESS CONCENTRATION ON A PLATE WITH HOLE

Objective: -

1. Compare the deformation and maximum stress developed on a structural steel model for the 2 cases.
2. From an analysis standpoint, select which of the two design cases performed well? Explain why?
3. From a manufacturing standpoint, which of the design will we select?

CASE-I

Procedure: -

• Open the Ansys workbench and select the static structural analysis system.We can rename it as "plate with a hole".
• If we want to add any other material we can right click on engineering data and edit it to add materials. Structural steel material will be loaded by default, and if we want to load more materials we can choose from Engineering data source>General materals.

Geometry-

Create a plate in spaceclaim with dimensions:

Length=300mm
Height=120mm
Thickness=30mm
Circular Hole at the center:
Diameter=60mm

Meshing-

• A mesh size of 2mm is provided to the plate.

Boundary Conditions: -

• Apply a load of 500N on the right face of the plate.

• Fix the left end of the plate

Results-

Equivalent stress for the first case: -

Total deformation for the case-I

CASE-II

Geometry-

Plate dimensions:

Length=300mm
Height=120mm
Thickness=30mm
Circular Hole at the center:
Diameter=60mm

Smaller holes 90mm away from the center:

diameter= 30mm

Meshing-

A mesh of size 4mm is applied to the plate as we have elements count limit for the academic version.

• Same as case 1 we applied 500N of force to the right face of the plate.

• We fixed the left face of the plate.

Equivalent stress for the second case: -

Total deformation for the case-II

The below table consists of all the results of the analysis: -

Results	Maximum equivalent stress (Von-mises)	Total deformation
Case-II	0.57771 MPa	2.973e-4 mm
Case-I	0.60616 MPa	2.7492e-4 mm

CONCLUSION: -

• From a manufacturing standpoint we will select the first case analysis i.e plate with a hole because it will be easy to manufacture than the other.
• From an analysis standpoint we will select the second case i.e plate with three holes because it will experience less equivalent stress. The stress concentration around the bigger hole is less due to the presence of smaller holes.Also we get to learn about variation of the stress and deformation throughout the body in this case.