Assignment 2

ASSIGNMENT 2

OBJECTIVES:

1. Check the material properties of the rail component and calculate the speed of sound in steel rail= 5188.75 m/s

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. = 0.192 ms

3.Time for sound to travel length of rail=0.192 ms

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)

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.

PROCEDURE:

• Import the given three model files in hypermesh.

• We have three methods to form the 3D tetra mesh in hypermesh
• Tetra mesh: using surface.
  1. Delete the solid if any in the model delete- solids.
  2. 2D mesh the surface of the component with required element size, 2D – automesh – trias.
  3. Check the element min and max size to have the control over the tet collapse in 3D mesh.
  4. Then 3D- tetramesh – tetramesh – elem – mesh.
  5. In teramesh parameter give min and max elem size and tet collapse value to have a control over the mesh.
  6. Finally delete the 2D mesh.

• After the mesh to check the tet collapse go to tool – check elem – 3D – tet collapse.
• Tetra remesh is used to re mesh the tetra elems 3D- tetramesh – tetra remesh – elem – free boundary face (remeshable) – remesh.
• Tet collapse nothing but height of the mesh we can change the height using geom – distance – two nodes – change the distance limits.
• Tool – reflect – node / axis – base node – reflect to make replica the elems, make sure you have duplicate the elems in the current comp.

• Hexa mesh:
  1. Delete the solid if any in the model delete- solids.
  2. 2D mesh the surface of the component with required element size, 2D – automesh – quad.
  3. go to 3D – line drag – select the elements – line to drag the hexa elements.
  4. Then go to – 3D – spin – spin elem – select the elements to spin – axis/nodes and centre point – angle – spin+/-.
  5. Then go to 3D – linear solids – from elem – alignment nodes – to elem – alignment node.

RESULT AND CONCLUSION:

• Learnt to do 3D tetra mesh and hexa mesh using different methods and how to control the tet collapse and reduce it.

https://drive.google.com/file/d/1WxW6slYAbfBDzkjtGQRG-bHC_fe5T6_J/view?usp=sharing