Analysis on a plate with a hole using Solidworks

AIM

To design and perform a static analysis on a plate with having holes for different case

Case1. Rectangular plate with centre hole

Case2. Rectangular plate with 3 holes

INPUT FOR SIMULATION

INPUT	VALUE
Material	Alloy steel
Mess size	2mm
Load	1000 N
L x B x H	300 x 120 x 30 mm3
Centre hole	60 mm diameter
Fixed	At small face

GIVEN

The dimension of the rectangular plate is as shown in the figure below

Case1. Rectangular plate with centre hole

Case2. Rectangular plate with 3 holes

BODY OF CONTENT

Introduction

To improve the economy of shipbuilding, holes are installed in some hull structural areas during ship construction. Additionally, setting personnel or equipment channels in certain parts is necessary for satisfying requirements from the rules and the ship-owners. However, when the hole in the plate is subjected to external loads, stress concentration is inevitable owing to the discontinuity of the structure. Excessive stress around the holes puts the plate in a yield state or produces cracks, causing structural damage and reducing the service life of the structure.

STEPS FOR DESIGNING

Before starting drawing make sure that the unit system is in mm.

Case1. Rectangular plate with centre hole

1. Firstly, draw the sketch and provide the dimension according to mention in the figure below. Make sure that the design is closed.

2. Now go to the extrusion feature and give the extrude dimension of 30mm.

3. Now the final design of the plate with hole is as shown in the figure.

Case2. Rectangular plate with 3 holes

1. Firstly, draw the sketch and provide the dimension according to mention in the figure below. Make sure that the design is closed.

2. Now go to the extrusion feature and give the extrude dimension of 30mm.

3. Now the final design of the plate with hole is as shown in the figure.

STEPS FOR FEA SIMULATION

For doing FEA analysis in Solidworks make sure that the simulation is enable in Add ins of the Solidworks.

The process for simulation is same for above two cases. I will discuss the steps of FEA analysis for only one case.

1. Firstly, click on simulation option after that go to the new study option as mention in figure with the red colour.

2. Now the select the type of analysis which you want to do like static, dynamic etc as shown in figure after that click on ok button. Here I am going to study for static analysis.

3. Now you will enter in the window which you have selected for the analysis as shown in the figure below.

Now the option which we have to provide for doing analysis is highlighted with the red colour box in figure below. Both red colour box represents the same option.

4. Now right click on double hole part option and select apply material option as shown in the figure below.

5. After that one dialog box will appear, choose the material from the dialog box as per your requirement and click on apply button. Here I used alloy steel for the material. When you click on the apply option the colour of your design will change.

6. Now right click on fixture option and select the type of fixture which you want in your design as shown in the figure below. Here I am using fixed geometry to fix the one face of the rectangular plate in order to make it free at one end and click on ok button.

7. Now right click on external load option and select the load type which you want to apply on your design. Here I used the force option for 1000N force which is applied on the face of the rectangular plate as shown in the figure below.

8. For meshing of the design we need to right click on mesh option and click on create mesh. After that there is two way to do meshing one is automatic and second is manual. Here I used for manual method and provide the size of mesh as 2 mm as shown in figure. Smaller the mesh size will give you more accurate result.

9. Because of meshing of the rectangular plate, it looks different from the previous figure as shown in figure.

10. Now right click on the part and click on run option. The name may vary according to your design but to run the simulation we need to follow this step. When you click on run button it starts the simulation.

11. After completing the simulation the result will be displayed on the screen.

RESULTS

Case1. Rectangular plate with centre hole

Mass - 7.66286 kg

Volume - 0.000995177 `m^3`

Density - 7,700 `(Kg)/m^3`

Weight - 75.0961 N

Material Properties

Model Reference	Properties	Components
	Name: Alloy Steel Model type: Linear Elastic Isotropic Default failure criterion: Max von Mises Stress Yield strength: 6.20422e+08 N/m^2 Tensile strength: 7.23826e+08 N/m^2 Elastic modulus: 2.1e+11 N/m^2 Poisson's ratio: 0.28 Mass density: 7,700 kg/m^3 Shear modulus: 7.9e+10 N/m^2 Thermal expansion coefficient: 1.3e-05 /Kelvin	Rectangular plate with centre hole

Stress plot

Displacement plot

Strain plot

Case2. Rectangular plate with 3 holes

Mass - 7.33629 kg

Volume - 0.000952765 `m^3`

Density - 7,700 `(Kg)/m^3`

Weight - 71.8957 N

Material Properties

Model Reference	Properties	Components
	Name: Alloy Steel Model type: Linear Elastic Isotropic Default failure criterion: Max von Mises Stress Yield strength: 6.20422e+08 N/m^2 Tensile strength: 7.23826e+08 N/m^2 Elastic modulus: 2.1e+11 N/m^2 Poisson's ratio: 0.28 Mass density: 7,700 kg/m^3 Shear modulus: 7.9e+10 N/m^2 Thermal expansion coefficient: 1.3e-05 /Kelvin	Rectangular plate with 3 holes

Stress plot

Displacement plot

Strain plot

Table for static analysis result

Properties	Rectangular plate with centre hole		Rectangular plate with 3 holes
	Max	Min	Max	Min
Stress	1.212 MPa	0.014 MPa	1.161 MPa	0.001 MPa
Displacement	0.000524 mm	0	0.000567 mm	0 mm
Strain	0.000004747	0.0000001236	0.000005	0
Mesh size	2 mm		2 mm
Total Nodes	1007280		949026
Total Elements	719822		675004
Load	1000 N		1000 N
Material	Alloy steel		Alloy steel

CONCLUSION

1. The Von mises stress generated in the plate having single hole is greater than the plate having 3 holes.
2. The strain and displacement are greater in the plate having three holes as compared to plate having single hole but their difference is very small so can say that it is almost equal.
3. The weight of the plate having three holes is less than the weight of the plate having single hole.
4. Extra hole helps in stress relief factor.
5. Plate having three holes is much more effective to use as compared to plate having single hole.

REFERENCES

1. skill lync video lecture