Its probably me but i can run snappyHexMesh but once my pisoFoam is done running i get a cell mismatch error

Perfect - could you provide the relevant part of the error message?

Hi everyone, I've been reading up on the kOmegaSST model, and I can't find the justification for the modification of the sigma_k1 coefficient. Menter's paper just basically says "change 0.5 to 0.85 and you're good" but I want to know where that comes from.

I can't actually seem to find it explicitly stated anywhere

That guy

I dont know the source, but it was likely tweaked to better fit some experimental data right? Something with k. Not sure if it's needed to dig deeper, most (all?) of these coeff are empirical

Yeah that was my suspicion. The problem and the reason I'm looking into it, is because I want to replicate a paper where someone modified the constants for kOmega. I wanted to then translate that modification to the SST model.

e.g. if you change sigma_k1 in the baseline model from 1 to 2 for instance, how should sigma_k1 in the SST model change

I was hoping there was some relation that I could use to be consistent

But if that relation doesn't exist, I might just have to not modify sigma_k

the choice feels very random, see this for example

everyone seems to root for his own coefficients

this report is quite helpful, thanks

Yep, extremely random....

Well, I've seen quite a few people say the results aren't very sensitive to it, so guess I can probably keep it at 0.85 and be safely within the range of 0.3 to 1

"Wait, it's all just made up arbitrary coefficients?"

"Always has been"

but that's good news, actually, right?

no major screwup (on account of that coefficient, at least)

Yeah guess it depends how you look at it

But clearly it must do something, otherwise what's the point in changing it between baseline and SST

Unless menter just happened to wake up on a different side of the bed, there must be something about the modification to the eddy viscosity that made the change to the Schmidt number a good idea

Eh, for now I'll leave as is and will just do a sensitivity study down the track

the modification of other terms may have changed things that can be re-calibrated thanks to this (these) coeffs

Going from baseline to SST, the only thin that seems to change (other than Schmidt number) is the formulation of the eddy viscosity, where rather than k/w its ak/max(aw, f2*Om)