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

1) Calculate the speed of sound in steel rail

Sol: Formula for "Speed of sound" C= √ E/ρ

from the given 0000.rad file we can get the material properties of steel rail From the above image

we can see the value of E=210000 Mpa(N/mm^2) ρ =0.0078 g/mm^3, now using the above-mentioned formula, we can substitute the values and get the speed of light i.e,

c= 210000/0.0078 =5188.75 m/s

2) Calculate the time taken for the shock wave to cross the rail of 1000mm Formula for the time taken t=l/c

t=1/5188.75 =0.1927ms(milliseconds)

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

4) The engine file edited according to the above-calculated values, its shown in the below image

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

Total Frequency =Terminated time/Number of animation steps.

=0.192/20

=0.0096 HZ.

set the above-calculated frequency in 0001.rad file(import the .rad file into the software and edit the cards) like shown below

6) Set the N_print value as -10

• Now after changing all the values Export the solver deck file in .rad format

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• The above image is the final radios engine file after making all the changes
• The same radios file is attached in the challenge asset

Objective:

• To mesh the given file and connect it by anyone 1D connector

Steps:-

• Directly open the .hm file into the software
• Mesh both the surfaces
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• Go to 1D>connectors>rods select any two nodes to connect.

• Now the connection is done after which a new property card should be assigned to the component with property card image of "P_ROD"

• New hyper beam has to be created, go to hyper beam and select required cross-section and give the required dimension as shown below

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• The final result is shown in below image
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Steps for 3d tetra mesh model:-

• Open the model directly since it is in .hm format
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• Check for any geometrical error, in this case, we don't have any so carry on with 2d mesh first
• Mesh each component according to the given quality criteria with tria elements
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• Now we have to convert the 2d mesh element to tetra elements by 3d>tetramesh select the elements and mesh with the required tet collapse value
• Do the same to the other components and make sure no tet collapse errors should be present
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Steps for 3D Hexa mesh 0f arm bracket model:

• In this model, we have four components, one by one we will be meshing the model
• We have different methods to perform 3d Hexa mesh-like Element offset, spin, Linear solid, solid map...etc
• We will be using these methods to perform Hexa mesh on each component, depending upon the geometry of the component.
• Firstly the base, it is just a rectangular cube it is better to mesh the top surface with only quad elements and use the element offset option.
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• The next component is the curved arm, to mesh this model select the common 2d element between the base and arm curve component, spin the element using the base node and axis to rotate.
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• To mesh the arm straight component, use the 3d>linear solid option.
• We should mesh each end by 2d element and join the same in this method.
• Already one end of arm stright component is meshed by Hexa element, to extract 2d element from Hexa element, go to tools>faces extract faces option.
• One end of the component will have 2d elements, mesh the other end with the same number of elements to avoid Penta elements.
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• To mesh the boss component we will be using the Solid map option.
• Mesh the boss on one side and solid map the element to the other end by nodes.
• Now after meshing all the components by Hexa elements we have to delete all the 2d elements present in the model.
• Go to delete option select elements by config option and select quad 4 elements, now all the 2 elements will be deleted.
• Final image as shown below.
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CONCLUSION:

• Understood how to calculate the speed of sound in different materials, frequency, time steps.
• Got to know how to create 3d tetra mesh and Hexa mesh.
• Learn how to give different types of 1D connection and hyper beam concept.