Crash Worthiness Analysis using HyperMesh and Radioss

OBJECTIVE:

The main objective of this challenge is to carry out the geometry clean up and perform meshing by extracting the mid surface according to the given target length

PROCEDURE:

1. GEOMETRY CLEAN UP
2. EXTRACTION OF MID SURFACE
3. CLEAN THE MID SURFACE GEOMETRY
4. CREATE 2D MESH AND ELIMINATE ALL MESH ERRORS
5. ASSIGN PROPER THICKNESS

GEOMETRY CLEAN UP:

• Open the hypermesh software and select the RADIOSS mode in the USER PROFILES window
• Goto IMPORT SOLVER DECK -> IMPORT GEOMETRY and make the file type in IGES mode and open the file and then click on IMPORT
• File is successfully imported to hypermesh
• Make sure the file opened is BY 2D TOPO to make topological corrections
• Goto QUICK EDIT -> by using WASHER SPLIT/TOGGLE EDGE/FILLER SURF/ADD or REMOVE POINT we have to make corrections
• Goto SURFACE EDIT -> UNTRIM SURFACE or PLANE to intersect two planes or surfaces and delete the unwanted surface
• Use FILLER SURF to fill holes
• Click on RETURN to exit from tool after the corrections is done
• Repeat the same procedure for other three models

MODEL -1

MODEL -2

MODEL -3

EXTRACTION OF MID SURFACE:

• After all geometry clean up is done Goto MIDSURFACE -> select MODEL -> then click On EXTRACT
• Mid surface extraction is done and click on RETURN
• Repeat the same procedure for all three model

MODEL -1

MODEL -2

MODEL -3

CLEAN THE MID SURFACE GEOMETRY:

• After extracting mid surfaces of three models we have to check for any errors is there
• If any remove errors by keeping model in GEOMETRY mode for all three models
• TOGGLE the unwanted lines which is not necessary in geometry to achieve given quality criteria

CREATE 2D MESH AND FOLLOW QUALITY CRITERIA:

• Make sure that the GEOMETRY is in mixed mode and ensure after extracting mid surface we have to keep in 2D for meshing
• Now press F12 and give the target element size as 5mm mesh type is mixed and give the criteria for max and min length errors by using BATCHMESH/QI OPTIMIZE and then by EDIT CRITERIA
• Now click on mesh by keeping cursor on SIZE AND BIAS to get preview of mesh
• Now we can edit the MESH by increasing or decreasing the no of nodes according to our criteria
• Click RETURN and mesh is done
• Now check for quality errors
• Click F10 and set min length as 3.5mm and max length as 7mm
• Then goto QUALITY INDEX -> check for quality if not ->use CLEAN UP TOOLS -> PLACE NODE/ELEMENT OPTIMIZE/DRAG TRIA ELEMENT/SPLIT QUAD ELEMENT /COMBINE TRIA ELEMENTS to improve mesh Quality and flow
• Also use ELEMENT CLEAN Up/REBUILD MESH / DELETE or CREATE ELEMENTS
• Repeat the same for three models

MODEL -1

MODEL -2

MODEL -3

ASSIGN THICKNESS TO THE MODEL:

• Goto MODEL-> COMPONENTS-> Select MESH of MID SURFACE and down click on PROPERTY ID assign it
• Goto PROPERTIES-> assign thickness as 1mm
• Goto 2D TRADITIONAL ELEMENT REPRESENTATION-> DETAILED 2D ELEMENT REPRESENTATION it will show the thickness of mesh
• Repeat the same procedure for all three models and save the models

MODEL -1

MODEL -2

MODEL -3

CONCLUSION:

• Geometry clean up for all three models is done
• Extraction of mid surface is also completed
• Reduction of minor errors in geometry after extraction of mid surfaces also done
• 2D mesh on mid surface by giving target length and mesh type is also done
• Elimination of min length and max length errors to improve mesh quality is done by using several tools
• Assign thickness to the mesh models is also completed

Crash Worthiness Analysis using HyperMesh and Radioss -> https://drive.google.com/open?id=10VX91s6OM5KjUwkp2IkxkYi7FGHrW_Wr