Pressure cylinder with internal filleted radius

Prof. CharltonS. Inao

Defence Engineering University

Bishoftu,Ethiopia

Problem Definition:Find the DMX, maximum displacement ,SMN, minimum

stress and SMX, maximum stress for the gas pressure cylinder subjected to 35 Mpa internal pressure, young’s modulus of elasticity is 200 Gpa, poisson(v) ratio is 0.3. Illustration/figure is provided.

Cylinder Dimension:

Outside Diameter: 200, Height: 400

Inside Diameter: 150

Wall thickness : 25

Fillet Radius: 25

Quarter of a gas pressure cylinder

Half of gas cylinder in 3D wireframe

Preprocessing

Define ElementPreprocessor> Element type>Add>Element type>Solid>Tet

10 Node 187>Ok>Close

Element type=>Solid,Tet 10 Node,187

Solid, Tet 10 Node, 187

Element >Options>Pure Displacement>Ok>Close

Real constants>Solid 187 element type does not require real constants

Apply Material Properties…Preprocessor>Material Props>Material Models>Material Model

No.1>Structural>Linear>Elastic>Isotropic>Input Value for Elasticity and Poisson Ratio

Modulus of Elasticity=2e11 0r 200e9Poisson Ratio= 0.3 normal value for steel,

then click OK

Keypoints x y z1 75 0 2 100 0 3 100 200 4 0 200 5 0 175 6 50 175 7 75 150 8 50 150

Modeling PhaseInput key points in active coordinate

System, the x and y coordinates

Modeling Phase

Your Screen should look like this

Modeling>Create>Lines>Lines>Straight Lines>pick

Pick KP1 and KP22 and 33 and 44and 55 and 6 1 and 7

Creating Straight Lines

Creating Arc ,=>LARC,6,7,8,25

Create area arbitrary by lines.

Extrude Area about an axis,90 degrees

Quarter of gas cylinder rotated about y axis(90 degrees)

Apply mesh size controls>Preprocessor>Meshing>Size Controls>Smart Size>Basic>Size level> 3

Apply mesh on volumePrerocessor>Meshing>Mesh>Volume>Free

>pick all(all the volume)

Solution Phase

1)Apply BC(constraints)2)Apply 35Mpa on the concerned internal area

Solution>Define loads>apply>Structural>Displacement>On

AreasClick Plane yz>Ux=0

Solution>Define loads>apply>Structural>Displacement>On

AreasClick Plane yx>Uz=0

Solution>Define loads>apply>Structural>Displacement>On Areas

Click Plane xz>Uy=0

Apply pressure on the concerned area

The End