Assignment 2

Questions :-

1. Check the material properties of the rail component and calculate the speed of sound in steel rail.

Solution:-

Youngs Modulus of Steel, E = 210000 G/mm^2

Density of Steel, ρ = 0.0078 G/mm^2

Speed of the sound, C = ?

As we know that, C = √E/√ρ = √210000/ √0.0078

∴ C = 5188.74 mm/sec

2. The length of the rail is about 1000 mm.calculate the time takes for a shock wave to travel from one end of the rail to the other.

Solution:-

Length of Rail, L = 1000 mm.

Speed of sound, C = 5188.74 mm/sec

As we Know that, △t = L/C = 1000/ 5188.74

∴ △t = 0.19272 sec

3.Time for sound to travel length of rail = △t = 0.19272 sec

4.Edit the engine file so that the stress wave can be monitored, moving from one end of the rail to the other during impact -this will require a termination time equal to the time it takes for the sound to travel the length of the rail(set on/RUN card)

5.Set the frequency of animation output to a time that will give 20 animation steps(/ANIM/DT)

Solution:-

Frequency of Animation, f = 0.19272/20

∴ f = 0.009636 Hz.

6.Change /print -10.

7.3d meshing tetra mesh and hex mesh

• Repeat class examples and, maintain the quality.
• Target tet size=5mm,hex size=10mm,tet collapse=0.15

Solution:-

1st of all, we need to import the model which is in .hm formate.

Now, for mesh the base plate, hide all other bodies. keep the base plate as "current object".

Mesh to Base Plate :-

2D > automesh > select the upper surface of base plate > Mesh type "quad" , element size 10 mm > generate mesh > select the side surface of base plate no. of layers 5 as 25 mm of base plate > offst it.

Arm Curved :-

1. Hide the base plate, make the arm curve as current body.

2. first we need to get the center of the arm : 3D > drag the mouse pointer in arc > select 3 random points in arc > circle center.

3. 3D > Spin > Spin geom > 90 deg. > node list > select the 3 node in arc N1 N2 N3 (x-axis) > spin-

Arm Straight :-

1.Set the current component collector to arm_straight.
2. Go to the Automesh panel.
3. Select the three surfaces lying on the intersection between the arm_straight and boss components.
These surfaces are in the arm_straight component.
4. Set the meshing mode to interactive.
5. Click mesh to go to the meshing module.
6. From the Density subpanel, adjust the densities to obtain a mesh that matches the following image.
This mesh pattern matches the mesh pattern at the intersection of the two arm segments. This is
necessary for the next step.

7. Click mesh to update the mesh density.
8. Click return to create the elements and go back to the Automesh panel.
9. Click return to return to the main menu.

Boss :-

1. Set the current component collector to boss.
2. Automesh panel. > select the 5 surface of boss > mesh & maintain the mesh density.

3. To project mesh on other surface of boss :-

a. Go to the Project panel by selecting Mesh > Project > Nodes from the menu bar.
b. Select the to line subpanel.
c. Select the node on the rightmost top vertex, as per the following image.
d. Click nodes >> duplicate.

e. Click project to project the node to the line.
f. Click return to return to the main menu.

4. Solid map > destination geom. > select unmesh opposite surf of boss > element drag >mixed >path >select by node > select line > element size 10 mm > mesh

Meshed Component :-

After completing the mesh, check the tet collaps of 0.15.

Housing :-

Cover Mesh

View > Browser > Hypermesh > utility > Geom. Mesh > Quick Tetra Mesh > Vol. complis = comp.; min angle = 20deg. ; max. ang =80 deg. ; min. rev. angle = 150 deg. ; mesh size = 5mm ; mesh density = uniform ; Tet form = (Floating) ; Mesher = Automesh >> Mesh.

Quick Tetra Mesh does auto geometry cleanup before going 2D & 3D mesh.

Mask Cover

Hub Mesh

2D > automesh on surf. > type (trias with 5 mm mesh size) > Mesh

3D > tetramesh > fixed trias/quads to tetra mesh (elements) > tetra parameter > min. tet size = 3mm; Tet collaps = 0.15 > pyrimid trans ratio = 0.8 > Volume Tetra > (2D type = Tria; 3D type = Tetra; element order = First; Element size = 5mm; enclose volume = surf.) > Mesh.

Cover-Hub Mesh

Conclusion :-

Here we undrestood 3D tetra mesh & hex mesh with maintain the quality of the component, Quick Tetra mesh does the auto cleanup before going 2D mesh and 3D mesh.