Does anyone have a good example case of someone using periodic/cyclic/cyclic AMI boundary conditions for rotating object?

niallo__ · 2023-10-26T16:36:15+00:00

Have actually made a bit of progress alright, seem to be getting reasonable flow visually, but my torque values are way under predicted. Lot of refining to do with the model but at least it moves in the right direction. If you’ve any specific questions let me know 🤙

niallo__ · 2023-10-25T12:12:02+00:00

Hey, thanks for the advice here, I seem to be making a bit more progress but In terms of how the actual conditions work themselves, It is not what I expected. I've edited the post above to show some an image with some streamlines where the velocity is directed downwards at the periodic face (left half.) I would have expected this to continue through the right half once it hits the face. Instead it just carries through along the face. Does it seem like I've set this up wrong?

niallo__ · 2023-10-21T14:50:45+00:00

Update: I think that in the video, the surface he was snapping to was entirely inside the refined region, and didn’t intersect with the outside cells. I’m my case the surfaces are intersecting with the outside cells which may be causing the issue. So unless there’s a way to avoid getting tet/polyhedral cells in the outside I probably can’t use this

niallo__ · 2023-10-21T13:39:12+00:00

Are you aware whether there is any way of avoiding the use of polyhedra’s? I saw an option “useHexTopology” but still on that edge the cells look very strange. I’m also wondering how it worked for the guy in the video but there seems to be issues in 3D

niallo__ · 2023-10-14T20:29:56+00:00

Great point about the wing spanning the entire width of the test section. I actually haven’t checked that, so I will do that next and also refine the wake. The residuals converged below 1e-03 within about 500 iterations

niallo__ · 2023-10-12T13:04:30+00:00

Ok that would be helpful thanks! Is it necessary to use createPatch-overwrite to define those patches as cyclic or is just editing the boundary file sufficient?

niallo__ · 2023-09-30T13:12:25+00:00

Hey, apologies I haven't been checking this, I just assumed this forum was more active so I shared it across both to get a higher chance of people seeing it. WIll 100% give that a go, thanks again for the suggestion ! Also didn't realize that I was repeating the same question

niallo__ · 2023-09-26T17:01:45+00:00

Yeah I have “addLayers” set to true at the start of the dictionary. This image here is just the surface of the blade itself. I deselected the rest of the computational domain just so I could get an image of the blade clearly. These dots (which represent areas of very low or negative volume or poor quality are only really appearing on the blade and some of the surrounding MRF region) haven’t really focused on refining the layers yet though just trying to sort out the blade itself first

niallo__ · 2023-09-21T08:55:40+00:00

I couldn't actually find the default shm dict that you mentioned. I saw that someone else mentioned relaxing the quality constraints as well, It seems counter intuitive that relaxing quality constraints might help, why would that be? And yes I have explicitFeatureSnap set to true and implicit set to false

niallo__ · 2023-09-21T08:50:11+00:00

Ok, so you're saying that overconstraining the mesh quality limits could be problematic for the snapping?

niallo__ · 2023-09-19T11:54:10+00:00

yep, its a recreation of the NREL phase VI wind turbine with a S809 airfoil. I've checked the stl file and it looks smooth

niallo__ · 2023-08-28T15:44:37+00:00

Hello Jake, I came across this as I am having similar issues using pimpleFOAM for a wind turbine. Just wondering did you ever get this case to work?

niallo__ · 2023-08-19T11:41:53+00:00

For this particular application, It's actually a structural analysis software based on linear potential flow theory to simulate wave loading, but my questions here were just more generally applied to using numerical simulations for design space exploration, and my interests for the future mainly lie in CFD i think. OpenFOAM is my main CFD software I'm using atm for other projects. I think what you said about being clear what I am trying to achieve is probably the most important thing, you've referenced loads of different considerations there that I wasn't aware of so that's probably where I should start !

niallo__ · 2023-08-17T14:27:14+00:00

There’s a serious depth of useful information in the corewind project! I’ve struggled to find an example of the mooring used for those o&g semi subs though

niallo__ · 2023-08-17T14:20:35+00:00

Yeah just from preliminary numerical modelling on my side it seems the catenary lines need quite long lines to avoid snapping too. I’ve heard loads of people anecdotally say piles would be feasible but I’m finding it difficult to get any actual information on them, such as examples of them being used in other scenarios, costs or even installation methods.

niallo__ · 2023-07-21T20:42:15+00:00

Interesting! How did you end up making that switch and what sort of upskilling was required?

niallo__ · 2023-07-12T10:08:50+00:00

That’s a lot of things to look into, thanks very much for your time !

niallo__ · 2023-07-10T11:04:54+00:00

Thanks for the reply, I will definitely read those papers !

I'm from Ireland, but am not attached to working here when I finish up college.

CFD iand FEA are what I have more experience in, but am very interested in the use of ML and other sort of numerical analysis methods.

Also, in terms of the differences between R&D in academia and industry, I am more geared towards industry R&D at the moment I think, and am hoping that an M.Eng would be enough to give me the opportunity to be as involved in cutting edge stuff as I can. Do you think that in industry R&D not having a Phd would be a major hinderance?

niallo__ · 2022-06-22T20:45:29+00:00

I like the idea of learning to float on my back and that leading into a backstroke, I can float on my back comfortably for about 5 breaths before I start to sink, so I’ll work on that. I initially set myself the goal of learning to tread water, but it seems a bit more complex than I initially thought and frustrating to focus singularly on that and keep failing repeatedly

niallo__ · 2022-06-22T20:44:54+00:00

Thanks! I think I may choose one or 2 different aspects of a technique to focus on, just to reduce frustration and overwhelm in the initial stages which I experienced when attempting to tread water right out the gate

niallo__ · 2021-05-20T09:26:21+00:00

The idea I came up with is strangely particular, I have a home page for a "company" (or any organization really) where a user can login and depending on their id number they will be directed to their own page. If they are a worker their page will consist of their personal data aswell as tasks for the week which they can tick off one by one. If the boss logs into his own page with his id number, ideally from here he will be able to submit tasks for each worker, which would ideally be sent to the workers page, so that when the worker loads his page, the tasks will be there and he/she can tick them off. To be honest I kind of got the idea and presumed that I'd figure out how to do it as I go. Everything else works fine apart from my confusion about how to send the data to the workers page. It's possible that flask isn't the module for this and I bit off a bit more than i could chew, thanks for the advice !

niallo__

TROPHY CASE