[petsc-users] PETScFE Point Source

[Sanjay Govindjee]

Wouldn't it make the most sense to do it in a variationally consistent 
manner

rhs_a = int{ N_a delta(x - x_o) }

where x_o is the location of the point source?

-sanjay

On 4/13/18 7:46 PM, Matthew Knepley wrote:
> On Fri, Apr 13, 2018 at 1:40 PM, Robert Walker <rlwalker at usc.edu 
> <mailto:rlwalker at usc.edu>> wrote:
>
>     Hello,
>
>     Is there an example of application of a point source in one of the
>     tutorial  PETScFE style examples? Ideally this would be some point
>     on the interior, and not necessarily on a boundary.
>
>     Thanks, and apologies in advance if this is a stupid question,
>
>
> No, good question. You would have to decide what that meant in FEM 
> terms. All the internal integrals are done
> with quadrature. So putting the source at a quadrature point would 
> work, although its a little difficult to know where
> they will be. You could smooth it out a little, and check coordinates 
> in the forcing function. Last, you could check
> for a "close enough" quadrature point and put it there. I think making 
> a slightly extended source is usually best.
>
>   Thanks,
>
>      Matt
>
>     Robert
>
>
>     Robert L. Walker
>     MS Petroleum Engineering
>     Mork Family Department of Chemicals and Materials Sciences
>     University of Southern California
>     ----------------------------------------------
>     Mobile US: +1 (213) - 290 -7101
>     Mobile EU: +34 62 274 66 40
>     rlwalker at usc.edu <mailto:rlwalker at usc.edu>
>
>
>
>
> -- 
> What most experimenters take for granted before they begin their 
> experiments is infinitely more interesting than any results to which 
> their experiments lead.
> -- Norbert Wiener
>
> https://www.cse.buffalo.edu/~knepley/ <http://www.caam.rice.edu/%7Emk51/>

-- 
-------------------------------------------------------------------
Sanjay Govindjee, PhD, PE
Horace, Dorothy, and Katherine Johnson Professor in Engineering

779 Davis Hall
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http://faculty.ce.berkeley.edu/sanjay
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Books:

Engineering Mechanics of Deformable Solids
http://amzn.com/0199651647

Engineering Mechanics 3 (Dynamics) 2nd Edition
http://amzn.com/3642537111

Engineering Mechanics 3, Supplementary Problems: Dynamics
http://www.amzn.com/B00SOXN8JU

NSF NHERI SimCenter
https://simcenter.designsafe-ci.org/
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