Creo 1.0 and ‘CAE and FEA workflow’

By Geoff Hedges | Published: May 19, 2011

At PTC, we think modeling paradigms that don’t work well together cause most CAD challenges. Creo, however, works across all the paradigms so users can move seamlessly from a parametric modeler to a direct modeler to 2D, etc. And that benefits everyone. In a recent article, for example, I showed how an organization using parametric modeling might use direct modeling to effectively handle last-minute design changes.  Here’s another example: The CAE and FEA workflow.

The workflow

Manufacturers typically use these steps to prepare, validate, and optimize a design:

Import components from multiple sources into one digital prototype – leverage data from multiple tools, locations, and formats into one master digital prototype.

Clean-up data from systems that don’t produce watertight solids, so that the master model is precise, and test results are reliable.

De-feature and simplify models for analysis.

Analyze and optimize the digital prototype for interference, clash, structure analysis, etc.

Capture issues and send the revised model back to its various sources.

With a parametric-based design process, those steps are complicated. CAE experts often find themselves overwhelmed by the complexity of the design software and turn to a 3D CAD expert to help with preparation and optimization of models from multiple sources.

How direct modeling impacts the workflow

Creo, with its direct modeling app, however, can make many of the steps more manageable.

Import: Creo uniquely offers import capabilities independent of the source and format, so you can easily and quickly pass models backward and forward from multiple sources and tools. CAE and FEA experts don’t have to worry about problems with data interoperability. And once they’ve imported data from outside sources, they can easily optimize the data as if it had been created natively.

Clean up. With imported data, direct modeling automatically recognizes key attributes of the imported data, making it easier to work with.  Assemblies and assembly structures, shared parts, surfaces, blends, and dozens of other features are all intelligently recognized.

Direct modeling software can also often assess the manufacturability of the imported models. While most 3D CAD systems produce watertight solids, in some cases only surfaces, sets of surfaces, or surface parts load into the system. Plus, anyone can accidentally create non-manufacturable solid models. With direct modeling, anyone can quickly find non-solids and clean up surfaces and create solids, so the design can be the basis of a precise and reliable digital prototype.

De-featuring. Often, the digital prototype is simplified and de-featured for analysis. With direct modeling, anyone on the team can remove blends, small holes, faces, features ,and other irrelevant geometry. You can even chop off geometry unrelated to your simulation or split models according to symmetry. Then, use Creo to automate simplification and de-featuring work. That saves time and repetition during the analysis cycle so teams can freely and frequently update and validate designs with no redundant effort.

Analyze. With the precise digital prototype ready, CAE and FEA experts choose from a broad range of studies available:

• Clash and interference analysis across the whole digital prototype . Clash and interference checking helps teams identify parts that may be in conflict with each other in the context of the master digital model.
• Simulation of moving mechanisms. Simulate motion, including assembly, disassembly, and mechanism studies for the digital prototype
• Standard analysis, including linear static, deformation, and stationary thermal analysis.
• Advanced analysis, including nonlinear deformation, transient thermal, vibration, and failure analysis

Optimize. With direct modeling, you can easily make changes to the model geometry to optimize it based on the results, and share the revised models with the design team as reference models.

Once the study is defined, your team can easily reapply it to a revised model, ensuring the optimized model works. CAE and FEA are just a sample of the processes done easier when your team can switch between parametric and direct modeling. I’ll tell you about several more in the weeks ahead.