본문 바로가기

카테고리 없음

Flat To Fem Pdf Download

Last night I tried answering a question I've had for a while- can you really do a proper FEA analysis using free (or at least very cheap) software? I've found myself recommending a couple of times to find a free FEA package for running an analysis on simple geometries, but I don't actually have first-hand knowledge towards that end.:uhh:So at home I did a little looking around online and found LISA , an FEA package that is able to solve a nice array of structural FEA problems (and some CFD it claims).

  1. From Flat To Fem

It's 'free' up to 1300 nodes, and $80 unlocks it completely. So I downloaded LISA and messed around with it a little bit; the geometry meshing interface isn't the best (no surprise, I'm used to operating ANSYS which is around $35,000 per seat) but it does have the capability of making a simple FEA model for a block or other geometries. There are also some good tutorials available on YouTube and elsewhere to allow you to follow along in some basic structural analyses. Overall it seems capable but it will take me a little work to get comfortable with the interface and starting a mesh from scratch (it's hard to go old-school carbureted beater when you're used to flying in corporate jets ). Broken​LISA is also able to import several different solid models including STEP, so my next question was can I find a simple CAD package (hopefully parametric) which is better in 3-D modeling and can export STEP for LISA. This basically mimics my at-work practice of modeling a design in Pro-E or SolidWorks and then import to ANSYS using parasolid or STEP. I ended up finding what I consider to be a nice little package on Sourceforge called FreeCAD (Broken) This was a big find IMO because its geometry modeling capabilities are well ahead of LISA and it enables you to model a geometry and then have LISA import and mesh it.Picture of FreeCAD interface.

I need to gain some better understanding of the units system as I think I'm off in there somewhere, but I thought the post-processing was good, had some nice-to-have display options, and makes overall output of the results easy to visualize (even has a video animation mode).So far, I'm liking what I'm seeing considering it's all free up to this point I don't currently have an imminent need for home FEA, but if I did I think I could recommend LISA for basic structural at least. The node limit for the free version is probably better suited for 2-D models, but $80 really is a steal and that would allow you to solve some simple problems that I could imagine coming up.I was happy with LISA's auto-mesh algorithm as well, importing the c-clip was as easy as opening it and setting a max element size. It automatically refined on curves, and put together overall a nice starting mesh (although it would need some refinement to get better stress results in the corners). This could be solved by meshing just the surface of the c-clip and doing a 2-D model, which I'll see if I can get done next.FreeCAD is also a big win in this I think, it's an effective tool that has most of the 'need-to-have' features in a 3-D parametric CAD modeling tool, and exports to STEP files for LISA. Its graphics are nice, the layout seems pretty intuitive, what else can I ask from a completely free piece of software?

On the topic of free or cheap engineering resources I like to take advantage of as well:Material properties:. nice website with many (unverified for the most part) material properties. Great resource for detailed material properties of engineering metals including Steel, Aluminum, Magnesium, and Titanium. Spec is 'cancelled' but still very relevant, and easily found as a legal free download (link provided at assistdocs.com).

Which leads me to. A great resource for MIL specs provided by the DOD. All MIL and FED specs are available as free PDF downloads (I can't believe there are sites out there that try to charge for them) with searchable OCR-scanned documents (or in some cases native PDF files). Very good resource for alternative specifications if you can't afford (or don't want to buy) specs from ASTM, ASME, SAE, ISO etc. All 'cancelled' specs in the database also reference the spec that supercedes it (and you can still download the latest version before cancellation).

A crowdsourced CAD model database hosted by the makers of Solidworks (but parts are also available in neutral CAD formats), a nice resource for a variety of CAD models with searchable tags. What's not to like about McMaster-Carr? They have a search engine that's best-in-the-business IMO, and they provide CAD models for a TON of stuff, mainly engineering component related (fasteners, components, etc.).

A great free resource provided by NIST with amazingly detailed thermodynamic properties of engineering fluids. A great resource for CFD properties! I eventually got to looking into Mecway and I feel I should say something about it here.

As a Lisa user, I have to say it's very impressive! It's clearly based on Lisa but absolutely full of enhancements even though it's the same price (both are now $100).

Flat To Fem Pdf Download

Things just feel more comfortable. Here are some differences I noticed:Using STEP files is easier. In Lisa, you had to scroll through a list of surfaces to find the one you want. On a complex model with hundreds of surfaces, that was sometimes very tedious checking them one by one.

In Mecway you simply click on it and apply a load or whatever right there.Everything has units of measurement now which is a real breath of fresh air. I was restricted to using pure SI in Lisa because it was 'agnostic' and didn't know anything about units.

But with Mecway you can make dimensions in mm and mix that with force in pounds then show the stress in psi or MPa.Mecway doesn't seem to use named selections anymore. This is a bit tidier because when you create a force it only adds a force, not an extra named selection along with it. There are also some new loads - an interesting one is frictionless which lets a surface slide in whatever direction it's at. With Lisa you could do this in theory using rotated coordinates on every node but it would be too impractical in most cases. Here's an image of it used on a screw head. It looks like it's working as expected with the head being pulled into the cone.

Other things it claims to have are a nonlinear solver and a higher limit of a million nodes which I havn't been able to test using the demo but will be fantastic since I was alway running into the brick wall of Lisa's much smaller limit (60,000?). I didn't try the nonlinear solver either.On the downside, the meshing is still a bit rough. Sometimes it created 'invalid topology' elements although instead of waiting till you solve it to discover the problem, it displays a red X on the invalid elements immediately.

Hi Guys I have just seen this post and as I used LISA a little bit and I acquired a licence for MECWAY I thought I will post few things.Main thing is the question of the topic: Is cheap FEA soft worth anything. If you look at Calculix, Elmer, OpenFOAM, Code Aster and Saturn you will realise that YES it is and it is used by big companies, even nuclear firms are developing one and using it for civil, structural and CFD analysis.- in LISA you can use any type of units but you have be consistent as just like doing analytical calculations, if you use wrong units in formula you will receive magnitude higher or lower results or just a scrap results. According to license LISA and Mecway are the same 100$ but just LISA allow you to use it commercially, in Mecway it's just for educational purposes or private without any commercial use, if you want one you have to spend 350$.

In LISA you are able to do most of the things that on Mecway you will do, there are couple enhancements as geometrical nonlinearity, compression constraint, elastic support, stress linearization graph and few more which would be hard to perform/apply in LISA or not possible at all. I am going to do some Creo Simulate comparison with LISA/MECWAY and other software to help in learning them and FEA itself and I have already done some comparison. Simulate has got some tutorials which were done professionally so I take results as correct. Please have a look at results and compare if 100$ is worth it's price.Comparison shows how close LISA and MECWAY are to Creo Simulate in this simple case with regards to stress and displacement. Creo is much more powerful and easy to apply boundary conditions but it doesn't do Flow Analysis for example and you can do it in LISA/MECWAY.

Results of LISA/MECWAY were indentical, the mesh was generated identically using the same setting of course as it uses Netgen for meshing. Mecway was created by LISA's ex-programer so this is why they are identical. I like in LISA adding faces, volumes, nodes to one section and couple other things but I have to admit that Mecway wen't forward so much in ease of use and that it looks very promising. Please have a look at my website, where I used LISA for some analysis structural, fluid and thermal transient for real and theoretical applications. I intend to use it more and will try to compare its functionality with Creo Simulate as I just started to go thorough it's training.

I will post in more detail comparison of LISA and Mecway to Creo and hopefully for some tough subjects which L/M are not capable to deal with eg. Contact analysis I wil try to go for Calculix/Elmer or eOOS. My web page is and of you want to have a look at some more free software please go here. Alongside courses that are available for MOOC platforms these days, you can also get a hands-on experience through SimScale.

From Flat To Fem

It is a cloud-based tool where simulations can be set up on a browser. It does not need the hassle of licenses or installations. It allows structural, fluid and particle simulations.SimScale offers a free version where one can get up to 3000 hours for computing. For the free version, the projects created are publicly available. However, if one would like to keep your project private, a is also available. There is also a two-week free trial for the professional version of the platform.The SimScale provide easy to understand materials to help with usage of SimScale platform. In addition, you can explore the, where there are loads of projects already available.