91–100 of 106 posts
I started my career doing FE modeling and analysis with ANSYS and NASTRAN. Sometimes I miss these days. Thinking about how to simplify a real world problem so far that it is solvable with the computational means available was always fun. Then pushing quads around for hours until the mesh was good had an almost meditative effect. But I don't feel overwhelmingly eager to learn a new software or language. Much to my sur…
I took a course in undergrad, and was exposed to it in grad school again, and for the life of me I still don't understand the derivations either Galerkin or variational.
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I kind of thought Neural Operators were slotting into the some problem domains where FEM is used (based on recent work in weather modelling, cloth modelling, etc) and thought there was some sort of FEM -> NO lineage. Did I completely misunderstand that whole thing?
Those are definitely up next in the flashy-new-thing pipeline and I'm not that up to speed on them yet. Another group within my company is evaluating them right now and the early results seems to be "not very accurate, but directionally correct and very fast" so there may be some value in non-FEM experts using them to quickly tell if A or B is a better design; but will still need a more proper analysis in more accura…
I've been a full-time FEM Analyst for 15 years now. It's generally a nice article, though in my opinion paints a far rosier picture of the last couple decades than is warranted. Actual, practical use of FEM has been stagnate for quite some time. There have been some nice stability improvements to the numerical algorithms that make highly nonlinear problems a little easier; solvers are more optimized; and hardware is…
Could you write a blogpost-style article on how to model the shallow water wave equation on a sphere? The article would start with the simplest possible method, something that could be implemented in short C program, and would continue with a progressively more accurate and complex methods.
I've been a full-time FEM Analyst for 15 years now. It's generally a nice article, though in my opinion paints a far rosier picture of the last couple decades than is warranted. Actual, practical use of FEM has been stagnate for quite some time. There have been some nice stability improvements to the numerical algorithms that make highly nonlinear problems a little easier; solvers are more optimized; and hardware is…
Could you write a blogpost-style article on how to model the shallow water wave equation on a sphere? The article would start with the simplest possible method, something that could be implemented in short C program, and would continue with a progressively more accurate and complex methods.
Typically, Finite Volume Method is used for fluid flow problems. It is possible to use Finite Element Methods, but it is rare.
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> The only new player seems to be COMSOL Ouch. I kind of know Comsol because it was already taught in my engineering school 15 years ago, so that it still counts as a “new entrant” really gives an idea of how slow the field evolves.
The COMSOL company was started in 1986....
But they changed to COMSOL because they didn't have the trademark in Japan and FEM also gave associations to the feminine gender.
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Could you write a blogpost-style article on how to model the shallow water wave equation on a sphere? The article would start with the simplest possible method, something that could be implemented in short C program, and would continue with a progressively more accurate and complex methods.
If you are interested in this, I'd recommend following an openfoam tutorial, c++ though. You could do SWE with finite elements, but generally finite volumes would be your choice to handle any potential discontinuities and is more stable and accurate for practical problems. Here is a tutorial. https://www.tfd.chalmers.se/~hani/kurser/OS_CFD_2010/johanPi...
What's unclear to me is how do I model the spherical geometry without exploding the complexity of the solution. I know that a fully custom mesh with a pile of formulas for something like beltrami-laplace operator would work, but I want something more elegant than this. For a example, can I use the Fibbonacci spiral to generate a uniform spherical mesh, and then somehow compute gradients and the laplacian?
I suspect that the stability of FE or FV methods is rooted in the fact that the FE functions slightly overlap, so computing the next step is a lot like using an implicit FD scheme, or better, a variation of the compact FD scheme. However I'm interested in how an adept in the field would solve this problem in practice. Again, I'm aware that there are methods of solving such systems (Jacobi, etc.), but those make the solution 10x more complex, buggier and slower.
I took a course in undergrad, and was exposed to it in grad school again, and for the life of me I still don't understand the derivations either Galerkin or variational.
I learned from the structural engineering perspective. What are you struggling with? In my mind I have this logic flow: 1. strong form pde; 2. weak form; 3. discretized weak form; 4. compute integrals (numerically) over each element; 5. assemble the linear system; 6. solve the linear system.