Assignment 2

Questions:

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

3.Time for sound to travel length of rail=______

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.

Answers

1. the speed of sound in steel rail= 5188.74 mm/ms
2. The time taken for a shock wave to travel from one end of the rail to the other = 0.1927 ms
3. Time for sound to travel length of rail = 0.1927 ms
4. engine file snippet
5. frequency of animation output to a time that will give 20 animation steps = 0.009635

.

Procedure for Hypermesh models

Part 1

• In the first step the model file is imported in the hm software using the import option available in the hm menu.
• After that the meshing is done on the unmeshed surface.
• Then we go to 1-D panel and start giving the various 1-D connections joining the two meshed surfaces.
• We gave 1-D connections like rigids , springs , spot weld , bar etc.
• Then the file is saved in the desired location.

Part_2

• In the part 2 once the geometry is imported the geometry is checked for open surfaces, duplicate surfaces and open edges.
• After that we set the global mesh size to 5 mm and started meshing the model.
• Initially we started meshing the outer surfaces of the geometry with tria and R-tria elements.
• Trims were taken at the required location to provide good flow and capturing of the model.
• The features like fillet and curved regions are captured with R-tria elements providing better capturing of the model.
• Flat regions are captured with tria elements.
• After capturing of all the surfaces in both the geometries (i.e. hub and cover) it is checked for free edges and t- connection and if found they were removed.
• Now the quality is checked using the quality panel and cleared.
• After this we go to 3D panel and select the tetra mesh option from the tab ,we select the elements and generate the tetra mesh for the 2-d shell tria elements into the current collector.
• Then we check the tet collapse for 0.15 and clear the quality.
• Then the file is saved in the desired location.

Part_3

• In the part 3 once the geometry is imported the geometry is checked for open surfaces, duplicate surfaces and open edges.
• After this we set the global mesh size to 10 mm.
• Then we start meshing the face of the first part using mixed elements.
• After that we go to solid map option in 3-D panel and then drag the elements about the line and create the solid mesh for base.
• Then by using line drag option using the face elements of the base components at the desired location we create the3-D mesh for arm curve.
• Then we use the face elements of arm curve on one end of arm straight and create same elements on other end of arm straight.
• After that in the solid map option we map both the face elements along the line guiding the path and creating 3-D mesh elements for arm straight.
• After that by taking proper trims and creating shell elements on the face of boss and then by using these shell elements and solid map option the 3-d mesh for boss is created.
• After this the entire solid mesh was checked for equivalence.
• Once the equivalence is done we delete all the 2-D elements and take the face elements of 3-d mesh.
• Now we check these face elements are making an enclosed volume or not and check them for free edges and t- connection if there is no free edge and t- connection and face are enclosing the volume then it is ok otherwise we have to remove it.
• After this we delete the face elements and check the 3-D elements for quality.
• Then the file is saved in the desired location.

Link for hm file- https://drive.google.com/drive/folders/1UKbdvkWOejwcI2tdg-qVbok7RcdoDU27?usp=sharing