[Getdp] Need some help

[Christophe Geuzaine]

matthieu.guillon wrote:
> Dear Christophe,
> 
>     I am a new user of GetDP, and I need to compute the propagation of 
> an acoustic wave inside a horn (with a non constant cross section along 
> the propagation axis).
>     The equation looks like this:
> 
>         d²P     dP       d(ln(S))
>         -----  - -----  *   -----------    + k²*P = f
>         dx²     dx         dx
> 
>     With mixed Derichlet and Neumann boundary conditions (Robin BC).
> 
> Please could you show me how can I write this in the right procedure ?
> 

Have a look at http://geuz.org/getdp/wiki/MicroWaveElectricField 
(username: getdp, password: wiki). The formulation you're looking for is 
similar to MW_e_2D. (MW_e_2D is actually for the electric field in a 2D 
electromagnetic wave problem, but the equations are the same.)

Good luck,

Christophe

-- 
Christophe Geuzaine
Applied and Computational Mathematics, Caltech
geuzaine at acm.caltech.edu - http://geuz.org