Assignment 2-RADIOSS Engine File Editing & 3D Meshing Challenge

Assignment 2

RADIOSS Engine File Editing & 3D Meshing Challenge

Objective: -

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 it 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=5 mm, hex size=10 mm, Tet collapse=0.15.

 

Procedure: -

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

Answer: -   Speed of sound

                                 c = √E/ρ     ………… (1)

                c = sound of speed,

                E = Young's Modulus,

                ρ = density. 

Open the file in Notepad. 

In the above image, we have value of E & ρ.

E=210000 Mpa(N/mm^2),  ρ = 0.0078 g/mm^2

Now, put this value in equation …… (1)

               c = √E/ρ  ………… (1)

                 = √210000/0.0078

                c = 5188.74 m/s

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

Answer: -

Given data: - L= 1000 mm.

Formula: - Speed = Distance/time

                  S = D/t…... (2)

Put these values in equation (2)

         t = D/s

        t = 1000/5188.74

       t = 0.1927 ms

 

3. Time for sound to travel length of rail?

Answer: -  t = 0.1927 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)

Answer: -

1.import the file.

Select _[FIRST_RUN_0000.rad] file and then import.

 

 

Now, edit the engine file. For that, go to cards folder.

Edit the ENG_RUN file & put Tstop= 0.1927

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

Answer: -

Formula: - frequency = 1/time

                   f = 1/t ……. (3)

                  f = 1/0.1927

                  f = 5.1894 Hz

Multiply frequency by 20

               f = 5.1894 × 20

               f = 103.78 Hz

6. Change /print -10.

After that, export the file.

 

 

Final engine file: -

 

Now, mesh the following models: -

1. 1D_element,

2. Housing,

3. Arm Brackets.

1D_element: -

1. Firstly, import the model.

Command: -{File>>open>>model}

Given Model: -

Now, mesh both the surface.

Command: - {2D>>auto-mesh>>select surface>>element size 10>>mesh}

 

 

After that, connect both the surfaces with any connectors.

Final Model: -

 

Now, mesh the model with 3D meshing with given quality criteria.

2. Housing: -

Now, mesh the cover by using volume tetra method.

 

 

 

Now, check the volume meshing is successfully done or not.

After that, check for Tet collapse.

Command: - {Tool>>check element>>3D>>Tet collapse}

Here, we have zero elements fail for Tet collapse.

Final cover model: -

 

Now, mesh the hub model.

Now, we use different method to mesh the hub, i.e.  2D to 3D tetra meshing.

For that, we mesh the model with 2D element and type tria only.

 

 

Now, make 2D element to 3D tetra element.

Command: - {3D>>tetra mesh>>tetra mesh parameters}

 

After that, mesh the hub.

 

 

Check the tetra meshing is done or not. By delete the element or mask the element.

Check the Tet collapse failed element.

Command: - {Tool>>Check element>>Tet collapse}

Here, we have some Tet collapse failed elements.

Fix this element by manually or tetra remeshing.

For tetra remeshing go to tetra mesh and select tetra remesh. Also unmask adjacent.

Command: -{3D>>tetra mesh>>tetra remesh>>element>>displayed>>remesh}

By manually, replace the node.

All the Tet collapse are fix.

Final Hub model: -

Final Model: -

 

3D Hexa Mesh: -

3. Arm Bracket: -

Firstly, check the geometry if there is a defect, then clean the geometry. Here, we have four components. 1. Base 2. Arm curve 3. Arm straight 4. Boss.

Start with base component.

Mesh the upper face of base component with element size 10 and mesh type mixed.

Now, convert 2D element to 3D hexa element.

Command: - {3D>>element offset>>solid layers}

 

 

After that, mesh the 2. Arm curve component. Mask the base surfaces. Also create base node by using arc center.

 

 

After that, use skin method for offsetting the element.

Command: - {3D>>skin>>spin element}

 

 

 

Now, mesh the Arm straight.

 

After that, create faces from arm curve elements.

Command: - {Tool>>Faces>>select comp>>find faces}

 

After that, use the linear solid for offsetting the elements.

 

 

 

 

After that, delete the faces.

 

Now, mesh the boss component.

Mesh the surface of the boss component.

 

After that, use the solid map for offsetting the elements.

 

Final Model: -

Learning Outcomes: -

1. We learn about how to calculate speed of sound by using material properties.

2. We learn about how to import .rad files as well as export .rad files.

3. We learn about different types of connections.

4. We learn about 3D tetra meshing with different methods.

5. We learn about Hexa meshing.

Conclusion: -

In this challenge, we edit the radioss engine file and mesh the components with 3D tetra and Hexa elements. Also connect the two surfaces with different connections.