Carmelo98 |
January 25, 2024 04:05 |
Quote:
Originally Posted by david_h
(Post 197407)
Alberto,
I agree with the above statements, if the "face area vectors" point outward from cell i,j.
If all the "face area vectors" are pointed either toward the right or to the top, then:
on face the between i-1 and i (i-1/2),
"pos" would return rho[i-1]
"neg" would return rho[i]
on face the between i and i+1 (i+1/2),
"pos" would return rho[i]
"neg" would return rho[i+1]
The above is for zero-order reconstruction. For "cell-based" higher order reconstruction (e.g. limited-linear), the face values would take the form:
rho_pos[i+1/2] = rho[i] + drho[i]*(x[i+1/2] - x[i])
rho_neg[i+1/2] = rho[i] + drho[i]*(x[i+1/2] - x[i+1])
where drho[i] is limited gradient of rho at cell "i"
Dave
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Good morning,
sorry to reopen this old thread, but I'm studying rhoCentraFoam and I would like to understand better how this solver works.
I can't understand when David writes:
Quote:
rho_neg[i+1/2] = rho[i] + drho[i]*(x[i+1/2] - x[i+1])
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I think "negative interpolation" interpolates from x[i+1], so that:
rho_neg[i+1/2] = rho[i+1] + drho[i+1]*(x[i+1/2] - x[i+1])
Is it corret, or am I missing something?
In general, refers to the article:
"Implementation of semi-discrete, non-staggered central schemes in a colocated, polyhedral, finite volume framework, for high-speed viscous flows" by C.J. Greenshields et Al.
it is explained how to compute positive interpolation of a general quantity:
where:
However I can't understand how to compute .
I hope someone can help me.
Thank you
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