STRUCTURAL ANALYSIS OF PLATE WITH SINGLE AND MULTIPLE HOLES

• Objective :

To design a plate with single hole and multiple holes and determine the stress concentration on the plate by conducting structural analysis using Ansys Workbench.

STRUCTURAL ANALYSIS :

• Structural analysis is the process of calculating and determinig the the effects of loads and internal forces on structure or object.
• The aim of the structural analysis is to design a structure that has the proper strength, rigidity, and safety.
• Structural analysis integrates the disciplines of mechanics, dynamics, and failure theories to compute the internal forces and stresses on the structures to be designed.

STRESS CONCENTRATION :

• Stress concentration is a location in an object where the stress is significantly greater than the surrounding region.
• Stress concentration occur when there are irregularities in the geometry or material of a structural component that cause the interruption to the flow of stress.

PLATE DIMENSIONS :

CASE - 1 : Plate with single hole

• Length : 300mm
• Height : 120mm
• Thickness : 30mm
• Circular hole located at centre : 60mm diameter

CASE - 2 : Plate with multiple holes

• Length : 300mm
• Height : 120mm
• Thickness : 30mm
• circular hole at centre : 60mm diameter
• smaller circular holes awat from centre : 90mm
• smaller holes : 30mm diameter

BOUNDARY CONDITIONS :

For both plates :

• Fixed support on the left face of the plate
• Normal force of 500N on the right face in +X direction

PROCEDURE :

STEP - 1 :

• Structural steel is assigned as the material of the plate by using the Engineering Data.

properties of structural steel

STEP -2 :

Using the space claim a 2D sketch of the model is made

2D of plate with single hole

2D of plate with multiple holes

STEP - 3 :

• 2D sketch was extruded into 3D model on which the structural analysis is to be done.

STEP - 4 :

• The model meshed with elements type of tetrahedral and sizing of 3.5mm to fit the nodes and elements for the limit of student version.

Mesh quality

Mesh Statistics

STEP - 5 :

• As per the above given boundary conditions the left hand side is assigned as the fixed support and the right hand side which is +X direction is assigned with the normal force of 500N.

• The solution is evaluated by considering two mechanical resposes i.e deformation and equivalent stress.

RESULTS :

TOTAL DEFORMATION :

EQUIVALENT(VON-MISES) STRESS :

CONCLUSIONS :

• By considering the soution of the both cases stress in case-1 is 0.6066 MPA higher compared to the case-2 i.e stress 0.58011.It is due to the creation of small holes near the large hole where the stress has uniform distribution than case-1 where the intensity of stress near the hole is more.
• By considering the values of total deformation the case-1 has 0.00027487 which is lesser than the value of case-2 i.e 0.00029717.It is higher in case-2 than case-1 due to the uniform distribution of stress in case-2.

SELECTION FROM ANALYSIS POINT VIEW :

• From the analysis point i would prefer the case-2 because the stresses induced in case-2 are less compared to the case-1 and the deformation is very small in case-2 compared to case-1 from the point of application to the the fixed support.

SELECTION FROM MANUFACTURING POINT VIEW :

• From the manufacturing point view i would like to prefer the case-1 rather than the case-2 because it is easier to punch one hole at the centre than the punching holes at different positions.it leads to increase in stress concentration in the plate by making making hole and it can break the plate.