Cavitation

Flow visualisation of a cavitating hydrofoil as part of a preliminary test validation study for a large numerical and physical research project.

PAM-STAMP - Component Chaining

Chaining Manufacturing Engineering and Assembly Prototyping

In the previous section, the fabrication of components including the physics of materials has been tackled. In an automotive manufacturing process, the components are then assembled in the body shop. Again, shape, material properties, and stiffness are modified in this process. Product and process architects would benefit from this information, if available at the right time. To provide this information at the right time is the goal of the Virtual Body Shop. In technical terms, distortion due to the assembly process and related assembly problems, the true point in the stress-strain space, stiffness properties, residual stresses, and remaining hardening capabilities are provided to product and process architects – at the right time.

Areas of initial penetration

Computed distortion after unclamping

Residual stress after assembly (spot welds): without forming history

Residual stress after assembly (spot welds): with forming history

The virtual assembly process is described hereafter and illustrated with a few milestones.

  • Structural steel sheet metal parts are formed by stamping simulation,
  • Parts are positioned on fixtures,
  • Contact interference is detected between stamped geometries,
  • Clamping tools are closed,
  • Contact and distortion is updated,
  • Effects of pin locators etc. are taken into account,
  • Spot welds join components,
  • Effects of gap closing and thermal shrinkage is taken into account,
  • Contact and distortion is updated,
  • Assembly is unclamped and final distortion / residual stresses / true point in the stress-strain space are computed and made available for any virtual investigation.

The benefits for product and process architects lie on hand:

  • Uncover positioning problems,
  • Study effects of pin locators, fixtures, clamps, welds, gaps between parts,
  • Find assembly problems and apply counter measures,
  • Save cost for prototyping and apply costly engineering only where necessary,
  • Improve virtual performance evaluations in the field of durability and crash behavior.

Concept Validation

Evaluated prototype – Courtesy Chrysler

Excellent correlation between computed and measured results – Courtesy Chrysler

PAM-STAMP Features