[petsc-users] Modify RHS values at each iteration

[TAY wee-beng]

Hi Jed,

I need a solve a Poisson equation, which is part of my finite volume CFD 
code.

The RHS terms are calculated from the velocity.

In the standard mtd, the RHS terms are calculated from the velocity, 
which then solves the Poisson eqn to get the pressure.

Now, to improve the accuracy of the pressure obtained, a paper suggested 
obtaining the pressure  from the velocity in 1 iteration. Then use the 
new pressure for the momentum eqn to get a more accurate intermediate 
velocity. The RHS terms are recomputed again using the new velocity, 
which is then used to calculate the new pressure. This cycle goes on 
until the pressure converges to a certain value.

Hence, I wonder what is the best way to do it.

Thanks!

Yours sincerely,

TAY wee-beng

On 21/11/2013 3:44 PM, Jed Brown wrote:
> TAY wee-beng <zonexo at gmail.com> writes:
>> Hi, in that case, do you want any suggestion? Is it possible to apply
>> the preconditioner only once at the start, and not at every intermediate
>> step?
> You'll have to explain what you are trying to do.