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DG convection diffusion

+1 vote

Hi,

I'm trying to construct the convection-diffusion operator with DG elements of order 0.
$$-\nu \Delta p + u\cdot\nabla p$$
where $u$ is a given continuous vector function of order 1.

I have had a look at the the undocumented example given but it is not clear that the equation is of the same form

asked May 12, 2015 by mwathen FEniCS Novice (710 points)
edited May 13, 2015 by mwathen

Hi,

Can you precise a bit what are the terms involved?

I assume that v is velocity and u the diffusivity, and that they are given before the definition of the CD operator (either by calculation or by an Expression), and that both u and v are vectors.

I also assume that p is a vector in order for the operator to be consistent (if p is a scalar then this is a sum of a scalar and a vector which is not consistent).

What type of mesh do you wish to use? If u and v are given and p is a vector then it shouldn't be hard to implement using def? Maybe I don't understand what you are requesting...

Here $\nu$ is the diffusivity coefficient and $v$ is the velocity vector.

$p$ is a scalar function.

I don't know how to set up the bi-linear form of the convection-diffusion equation with the jump conditions coming from the DG implementation

1 Answer

0 votes

I encounter the same problem.

answered May 14, 2015 by Hamilton FEniCS Novice (500 points)
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