Assignment 2

Objective 

The objective of the project is to calculate the time taken for the sound to travel and perform 3D mesh for the model.

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

Material properties

• E - 210000 N/mm2.
• Rho - 0.0078 g/mm3.

Speed of sound in steel rail (c)= (E/rho)^0.5

                                        = (210000/0.0078)^0.5.

                                        = 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.

Time taken = l /c.

                 = 1/5188.75

                 = 0.1927 ms.

3. Time for sound to travel the length of rail =  0.1927 ms.

4. The termination time must be equal to the time taken for the sound to travel the length of the rail.

The time taken is 0.1927 ms so the termination time is set to 0.1927.

5. Set the frequency of animation output to a time that will give 20 animation steps

The frequency value is (1/0.1927) *20 = 104 Hz.

6. Change /print -10.

7. 3d meshing tetra mesh

• The import the housing model using File --> Import --> model option. The model has no error.

                                                           a) Housing Model

• 2D mesh is created 2D --> Automesh --> Surfs. Trias elements are set as mesh type & element size is 5mm and mesh is done. 

                                                                 b) Hub 2D mesh

• 3D --> tetramesh --> Tetra mesh parameters are set as i) Min tetra size - 3mm ii) tet collapse - 0.15                                iii) Max tetra size - 7mm. 
• In tetra mesh the elements and simple pyramids are set and mesh is used 

                                                            c) Hub 3D mesh

• 3D --> tetra mesh --> volume tetra, the surface enclosed volume is set to the surface and for 2D mesh is set to trias & for 3D mesh is set to tetras. The element order is set to first order & element size is set to 5mm & click on the mesh.

                                                          d) Cover 3D mesh

 3d meshing Hex mesh

• The import the housing model using File --> Import --> model option. The model has no error.

                                                     e) Arm bracket model

• 2D mesh is created 2D --> Automesh --> Surfs. Quads elements are set as mesh type & element size is 10mm and mesh is done. 
• 3D --> elem offset, the 2D element to offset & element are selected. The number of layers is set as 5 & total thickness is set as 25 & click on the offset+.

                                                              f) Base 3D mesh

• 3D --> Spin --> spin elements --> 2D elements (selected the 2D mesh is created), the angle is set as 90 deg & for the on spin is value is set as 25. The x-axis is set where B selected for which the center of the arc is selected. The spin - is selected to create the 3D mesh.

                                                      g) Arm curve 3D mesh

• The 2D elements are created at the surface ends. The mesh density at the 2 sides is set to be equal. 
• 3D --> linear solid, from & to is the source & destination for which the 2D elements are selected. The alignment for the similar three nodes for the source & destination & density is set to 12 & click on the solids. 

                                                        h) Arm straight 3D mesh

• 3D --> solid mesh --> general, the source is set none the 2D elements the destination geometry is selected & mixed is chosen under which nodes for the alignment & lines to provide the path for the mesh flow.

                                                                i) Boss 3D mesh