Stress Concentration on a Plate with hole

Objective:

• To determine the deformation and maximum stresses developed in the two given cases.
• To compare the results of the deformation and stresses of the two cases.

Procedure:

• Open ansys workbench.
• Create a new project named " PLATE _WITH_ONE_HOLE" & create another project named "PLATE_WITH_THREE_HOLES".
• Open static structural analysis system.
• Using engineering data resources add the required material to the library for analysis.
• Right-click on geometry and select a new Spaceclaim.

• Create the sketch according to the given dimensions.

• Using the pull option extrude the sketch to a thickness of 30mm.

• Close space claim and right-click on the model and select update.

• Open ansys mechanical for analyzing the deformation and stress by applying boundary conditions.

• Repeat the same steps for the Case_2.
• Now mesh the components using tetrahedrons with an element length of 2mm.

• Now right click on analysis settings and insert fixed support on left side and force of 500N on right side.

• Now right click on the solution tab and insert total deformation and equivalent stress and evaluate the results.

DEFORMATION OF THE PLATE IN CASE_1

EQUIVALENT_STRESS_IN_CASE_1

TOTAL_DEFORMATION_IN_CASE_2

EQUIVALENT_STRESS_IN_CASE_2

COMPARISON BETWEEN CASE_1 AND CASE_2 :

SL.NO	CASE	CASE_1: Plate_with_one_hole	CASE_2: Plate_with_three_holes
1	TOTAL DEFORMATION (IN mm)	0.00027492 mm	0.00027928 mm
2	EQUIVALENT STRESS	0.6051 Mpa	0.58024 Mpa

• In CASE_1, Due to a hole in the center, there is maximum stress generated in the hole area.
• In CASE_2, Due to the three holes present one after the other the two holes at the ends will act as stress reducers. So that the stress will be distributed along the plate,So we will get less stress with stress distribution.

Conclusion:

• From an analysis standpoint, I will select a plate with three holes as in case_2

Because It creates less stress and has more life than a plate with one hole.

• From a manufacturing standpoint, I will select a plate with a single hole. Because the cost and time required for manufacturing is less.

If I select the plate with three holes I need two different diameter drill bits of sizes of 30 mm and 60 mm which will increase the cost of tools required for manufacturing and also the time for manufacturing increases. The scrap will be more when compared to case_1 is another reason.