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-   -   Something not clear for me in Jasak's thesys (https://www.cfd-online.com/Forums/main/13685-something-not-clear-me-jasaks-thesys.html)

 Lam June 20, 2007 03:53

Something not clear for me in Jasak's thesys

Hi all,

I've read the thesys of Jasak.

And in the part 3.8, when he speaks about the semi-discretized form of the momentum equation, I wonder where the "laplacian(nu,Grad(U))" is.

Because, he says: a_p*U_p=H(U)-Grad(p), where H(U)=-sum[a_n*U_n]+U0/deltaT

and div(UU)=a_p*U_p + sum[a_n*U_n]

First I guess that laplacian(nu,Grad(U))=a_p * U_p + U0/deltaT

But I'm quite not sure. Hope that somebody can tell me where the laplacian(nu,Grad(U)) term is, in the discretized form.

Lam

 Hrvoje Jasak June 20, 2007 06:16

Re: Something not clear for me in Jasak's thesys

Read it again: laplacian(nu,Grad(U)) also lives in a_p*U_p + sum[a_n*U_n], just like the convectin term - this is described in the discretisation chapter.

Hrv

 Lam June 20, 2007 06:38

Re: Something not clear for me in Jasak's thesys