Hi Ohi, comments below...
On Fri, Feb 10, 2017 at 10:47 AM, Ohiremen L Dibua <odibua@xxxxxxxxxxxx>
wrote:
Hello,you setting Dirichlet and extrapolate if you want Neumann?
I am writing to ask about the boundary conditions in overture. I would
like to implement a symmetric boundary condition. I am doing this for a
rectangle to test it out before doing it for a composite grid. Below is the
code for implementing the boundary conditions in my set-up. My thought is
to do so by using neumann BCs. The PDE I am solving is laplace's equation.
I make two of the boundaries periodic with:
map.setIsPeriodic(axis2,Mapping::functionPeriodic);
Then I implement the boundary conditions as:
Do you have boundaries with boundary conditions 1, 4, 5 ?? If so why are
coeff.applyBoundaryConditionCoefficients(0,0,dirichlet,1);
coeff.applyBoundaryConditionCoefficients(0,0,dirichlet,4);
coeff.applyBoundaryConditionCoefficients(0,0,dirichlet,5);
coeff.applyBoundaryConditionCoefficients(0,0,extrapolate,1);
coeff.applyBoundaryConditionCoefficients(0,0,extrapolate,4);
coeff.applyBoundaryConditionCoefficients(0,0,extrapolate,5);
After this, I implement the dirichlet BCs and then implement the Neumann
BCs. After doing these, I write:
getGhostIndex(mg.gridIndexRange(),side,axis,Ig1,Ig2,Ig3);
getGhostIndex(mg.gridIndexRange(),side,axis,Ip1,Ip2,Ip3,-1);
f(Ig1,Ig2,Ig3)=0;
The result is below. If I take a central differencing about it, the
derivative is 0, but the boundary itself is all 0s. I have looked through
the OvertureOperators guide, but haven't found help for this. Is my
implementation of a symmetric BC through Neumann incorrect?
...Bill
Thank you for your time,
Ohi
