Customer Modeling Requirements Customer Modeling Request
Finite Element Model
Rail parts meshed at 6mm average element size.
Typical BIW components are meshed with a 10.0mm element average length. However, as this model is shared amongst multiple load cases it is advised to mesh the critical load carrying rails with a refined mesh size. This approach allows critical areas such as crush initiators and strengthening beads to be captured thus optimizing a single model robust to handle multiple load cases.
Customer Modeling Requirements II
Areas of contact were modeled with matching meshes.
Scanned data (point cloud data) converted to STL format
STL data cleaned and prepared for converting triangle mesh into quad/tria mesh model
Final quad-tria shell mesh of average element size 10mm
Typical finite element meshing requires CAD data for best mesh quality results. Very often CAD data for the existing part is not available so it needs to be created from the scanned data. This CAD creation can be time consuming process. To avoid CAD creation for CAE analysis as a final product, STL format is directly converted to finite quad/tria shell element model. Mesh Model is then offset inbound by half thickness distance of the original scanned part. All element quality criteria's are met while elements are following the curvatures. Allowed Finite mesh to Scan data deviation is +-2mm.
Model Quality Required Values Aspect 85%<2:1 (not < than 10) 95%<3:1 100%<5:1 Warpage 15 MAX Skewness 45 MAX Quad Angle Min. 45 MAX Quad Angle Max. 135 MAX Tria Angle Min. 20 MIN Tria Angle Max. 120 MAX Jacobian SHELLS Not < than 0.7 Jacobian SOLIDS Not < than 0.5 % Trias 7 MIN LENGTH 1 TETRA COLLAPSE 0.2 Total Number of Elements 1135 # of Quads 1086 # of Trias 49 Model Validation Normal Modes Analysis Six Rigid Body Mode First Mode at 25 HZ
Customer Modeling Requirements Model CVT Housing Attribute NVH CAD data Provided by customer as IGES files Weld data Provided by customer Deliverable Transmission housing constructed with
solid and shell elements, correlated
to measured weights for each component
Quality Requirements Aspect 5:1 Warpage SHELL 10 Warpage SOLID 15 Skewness 45 Quad Angle Min. 45 Quad Angle Max. 135 (140-solids) Tria Angle Min. 20 Tria Angle Max. 120 Jacobian 0.6 Min. Length 4 mm Max. Length 15 mm % Trias > 5%
A combination of solid and shell elements were used to build the model. The weight of the finite element model was measured and correlated to the finite element model.
Customer Modeling Requirements
Customer Modeling Request