Stress Concentration on a Plate with hole using ANSYS Workbench

Objective: - Static structural analysis on a plate with a hole geometry

Case 1: Plate with a hole (increased thickness).

Case 2: Plate with multiple holes.

CASE 1: Design a plate with a hole model similar to what we worked in the class, but with increased thickness. Determine the maximum deformation and stress developed in the model.

Plate dimensions:

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

Material Selection: Structural Steel

Meshing: Element Size = 4 mm

Mesh Type = Tetrahedron

Boundary Condition: Force = 500 N (Right Side), Constrain on Left Side of the Plate.

1. Equivalent (Von Mises) Stress: Max. = 0.59153 MPa & Min. = 0.013929 MPa

2. Total Deformation: Max. = 0.0002712 mm & Min. = 0

CASE 2: Plate with 3 Holes.

Length=300mm, Height=120mm, Thickness=30mm

Dia. D=60mm at centre of the plate & Dia. d = 30mm, 90mm away from the centre.

Material Selection: Structural Steel

Meshing: Element Size = 4mm

Mesh Type = Tetrahedron

Boundary Condition: Force = 500 N (Right Side), Constrain on Left Side of the Plate.

1.Equivalent (Von Mises) Stress: Max.= 0.43293 MPa & Min. = 0.00092204 MPa

2.Total Deformation: Max. = 0.00022224 mm & Min. = 0

Compare the deformation and maximum stress developed on a structural steel model for the 2 cases

	Plate With 1 Hole (case 1)	Plate With 3 Holes (case 2)
Equivalent (Von Mises) Stress	0.59153 MPa (Max.) 0.013929 MPa (Min.)	0.43293 MPa (Max.) 0.00092204 MPa (Min.)
Total Deformation	0.0002712 mm (Max.) 0 mm (Min.)	0.00022224 mm (Max.) 0 mm (Min.)

Here, In Case 1 due to 1 hole in Plate there will be a sudden change in a structure of a plate and for that there is more stress concentration at hole.

And In Case 2 , there is 2 extra hole is added due to that plate get stiffer and stress is distibuted from center hole to two samller holes. So there will be a less stress in Case 2 with less deformation.

From an analysis standpoint, I will prefer a plate with 3 holes (Case 2), because its stress value & it’s deformation value is less as compare to plate with 1 hole (Case 1) and it will give better fatigue life.

From a manufacturing standpoint, I will prefer plate with 1 hole (Case 1) , because Case 1 need less manufacturing cost as compare to Case 2 ( due to extra 2 holes in Plate), So for Case 1, less time , Energy and less effort & wastage of material is there.