FEA Plan

[mechengdude]

I'm interested in getting feedback or pointed to resources pertinent to creating a "FEA Plan". What I mean by the term plan, would include a document used by an engineering department describing how FEA fits into an overall companywide Engineering Plan.

For example, I expect there will be some flow chart describing roles and responsibilities, the flow of requirements documents, etc. The intent is not to describe all the subtle nuances of what type of element shall be used for a certain analysis or what constitutes acceptable stress values etc.

Any suggestion appreciated.

Regards

 

[rb1957]

i think it'd either be a book of truly epic proportions or a simple statement "FEA is an technique that allows Engineering to assess the adequacy of our designs to fullfill the customer's requirements."

 

[mechengdude]

Ahhh...maybe I wasn't clear in my original post.

The intent is something similar to a Systems Engineering Plan found at this link and with the definition "The SEP is a "living" document that captures a program's current and evolving systems engineering strategy and its relationship with the overall program management effort. The SEP purpose is to guide all technical aspects of the program. It should be established early in the Concept Refinement phase and updated continually.'

https://acc.dau.mil/CommunityBrowser.aspx?id=29041

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[rb1957]

apologies in advance ...

apart from being a huge pile of Beautiful Script, i don't know that FEA is on the same level as Systems Engineering. i think the equivalent is Design Engineering, for which Stress Analysis is a component, and of whihc FEA is a component.

 

[GregLocock]

Grins, what he said.

Like any process there are inputs and outputs. These are provided from and to other people.

Often process people start from the inputs and work throught to the outputs. A better way is to ask who needs FEA (or more genrally structural analysis) output, at what level of fidelity, at what tme in the program.

Then give thiose requirements to an FEA bod who will be able to tell you what inputs he would need and when.

You'll almsot inevtiably discover that the structural analysis people need loads and so on long before they are available.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[SWComposites]

in my experience, FEA and Systems Eng have similar (large) piles of Beautiful Script, just from very different sources ...

you don't need an FEA Plan, you need a Structural/Thermal/etc Analysis Plan, of which FEA is just a tool to use in analysis.

structural analysis people will need a design, loads, material properties, test data to validate against long before they are available.

SW

 

[corus]

How about this wording :

The FEP is a "living" document that captures a program's current and evolving engineering design strategy and its relationship with the overall program management effort. The FEP purpose is to guide all technical aspects of the program. It should be established early in the Concept Refinement phase and updated continually.'





Tara

 

[mechengdude]

So far I'm taking a couple of things out of the responses and I'll attempt to paraphrase.

1. It's not just about FEA, it's about analysis in general with FEA being one tool. O.K. got it. So if I reworded the question to "Does anyone have experience writing an Engineering Analysis Plan or have any resources for said plan, please let me benefit from your experience". Would the responses have been any different?

2. The undertone of "Oh no, not another process to explain how we do things to the people that don't really care or have the capacity to comprehend it!" Yes I know I don't "need" the plan myself but it is being discussed as something "we" need. And yes I probably rolled my eyes when I heard the call to create an "FEA Plan".

Anywho...thanks for all your input. Maybe I can stall until someone tosses another shiny object into the air and all eyes focus on it and forget about this task.

 

[4Pipes]

NAFEMS have an extensive series of "how to" and good practice guides. These cover most things including the use of FEA within the wider design process.
The factor as hinted at above is always GIGO which needs specifying. You would also need to specify what is required and what it is to be used for. FEA is not always the most appropriate tool for the design objective. If you only want colored pictures, then getting them done by the local kindergarden would be the most economic option.

 

[rb1957]

i feel your pain, brother.

a major a/c manufacturer i was with spent years (and years) trying to process map the development of an airplane design. no surprise but i don't think they ever finished it, maybe another "bright shiny ball" came by to "refocus" their attention !

you could probably replace "Systems" with "Mechanical Design", or just "Design", or "Analysis".

 

[GregLocock]

All big car companies have a standardised template for developing a car and getting it into production. This specifies a series of gateways, and so far as analaysis goes tells me what results I am expected to have published, and what fidelity my model is, at each gateway (for instance for the first six months I am expected to be running hand analsysis and spreadsheets). The PDS actually specifies activities at a level of months (reasonable) weeks (optimistic) and there is even a daily breakdown. This is over a duration of two to six years typically.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[flash3780]

Uugh... I don't envy this task.

Many companies use FEA in two ways.

1. Design engineers create simple models to optimize the parts they design in conjunction with hand calculations. FEA is a tool that allows design engineers to produce more robust components. Design engineers also work with full time FEA analysts to plan more complex models.

2. FEA analysts (also engineers) work full-time creating complex models of systems of parts and models requiring advanced analysis techniques. FEA analysts usually belong to a separate "analysis group" who specialize in performing complex analyses. Often analysts specialize in things like thermal analysis, structural analysis, etc, especially in larger companies.

The process generally works something like this: The systems engineering group employs the project management group to coordinate the design of a module of a device (for example a suspension system in a car). The project management group goes to the design engineering group and requests a number of engineers to create a design. The first phase of the design (concepts, spreadsheet analysis, basic FEA, etc.) is carried out by the design engineers.

Once a preliminary design is established, the project management group, the analysis group, and the design group work together to determine areas requiring advanced analysis. The project management group requests analysis support for the required analyses. The analysis group validates the preliminary design produced by the design group. If issues arise, design iteration is required to correct the problems.

While the analysis group is working, design engineers begin coordinating drafting efforts, prioritizing parts by risk of modification (similitude to previous successful designs, etc). At this point design engineers spend a lot of time focusing on stackup analysis and the like, but must also address any potential problems identified by the analysis group (high stresses, thermal issues, etc). Particularly challenging design issues may require the analysis group to evaluate the resolution.

Once the design is deemed acceptable, analysis is no longer necessary. Although, thermal analysis is often calibrated to TC measurements on actual hardware in critical applications (aircraft turbine engines, etc). Sometimes failures are also evaluated with FEA to help determine root cause.

The whole design process involves a series of technical reviews (conceptual design review, preliminary design review, etc) which vary from place to place. These reviews involve presenting designs and design validations - which often involve presenting FEA.

I don't know if all that is helpful or confuses things... but maybe a few block diagrams later it will all make sense on a your flow chart.