Week 1 Stress Concentration on a Plate with hole

Q 11 Answer :

Objective:

1. To determine and compare the maximum deformation and maximum stress developed in two different cases.
2. To determine selection of Design from the Analysis and Manufacturing point of view.

Procedure:

Step 1: Engineering Data

• In this option you can find a list of generally used materials and you can add a material of desired choice/specifications.
• You can also add custom materials and specify the mechanical properties of materials.

Step 2: Geometry

• Select Static Structural Analysis and create the specified 2D geometry using spaceclaim.
• Extrude/Pull the geometry with given dimensions.
• Rename the Static Structural tab as Case 1 and follow the similar process for Case 2
• Update the Static Structural tab and proceed to model.

Step 3: Model

• In this step you can assign the material to geometry and generate mesh with desired accuracy of required solution.
• Within the Mesh option inside the Details of Mesh under default option you can specify Element size and see if the mesh quality is as per required standards.
• You also have an option to change meshing element type/meshing method according to requirements.

Step 4: Setup

• This step involves setting up boundary conditions and analysis settings
• Provide a fixed Support to the Left side face of plate.
• Prove a Force defined by components in the X-axis with given magnitude.

Step 5: Solution

• Observe results for Equivalent Stress distribution, Total Deformation

Observe for probes which point out Maximum and Minimum values of corresponding data.

**Note: Geometry procedure is same for both cases but with slight modification from case 1. Remember to add two holes in 2-D geometry before using the extrusion/Pull command.

Deformation and Stress results:

CASE # (500 N applied load)	Maximum stress (Von-Mises in MPa)	Maximum deformation (Total deformation in μm)
CASE 1	633.21	0.28955
CASE 2	333.96	0.17303

Images for CASE 1 & CASE 2 simulation results displaying Stress distribution and deformation:

Fig 1 showing areas of Maximum and Minimum stress in case1

Fig 2 showing areas of Maximum and Minimum deformation in case1

Fig 3 showing areas of Maximum and Minimum stress in case2

Fig 4 showing areas of Maximum and Minimum deformation in case2

Attached Simulation files display a detailed overview of preprocessing steps.

Results Comparison : In comparison, we see that stresses developed in the second case are 47% less than those in the first case. Also, the deformation produced in the second case is 40% less than that produced in the first case.

Q. From an analysis standpoint, which of the design will you select? Explain why?

A: Analysis shows that

-Design 2 is preferred as it produces less deformation and stresses than design 1 for the same amount of applied load and same material type.

-Also, stress concentration in design 2 is less than that of design 1.

Thus, design 2 is preferred as it performs better.

Q.From a manufacturing standpoint, which of the design will you select? Explain why?

A:From a manufacturing standpoint alone, selection will depend on the method used for manufacturing.

-Additive manufacturing methods like casting will consume less material for manufacturing design 2. So, design 2 will be preferred in this case. But if complexity of design for die casting mold and tooling is considered design 1 is preferred.

-In Subtractive manufacturing methods design 1 is preferred as it is easy to machine and has less cost of operation as compared to design 2.

Thus, design 1 is preferred in this case.