[linch]

Hi guys,

since OF 2.1 there is a new control structure for SIMPLE & PIMPLE loops. So now the outer PIMPLE loop looks just like:

while (pimple.loop())        {...}

I would like to know how to use it properly. I mean, how can one define convergence criteria for the outer iteration loop?

I tried to look into the pimpleControl.C and hier it is:

bool Foam::pimpleControl::loop()
00174 {
00175     read();
00176 
00177     corr_++;
00178 
00179     if (debug)
00180     {
00181         Info<< algorithmName_ << " loop: corr = " << corr_ << endl;
00182     }
00183 
00184     if (corr_ == nCorrPIMPLE_ + 1)
00185     {
00186         if ((!residualControl_.empty()) && (nCorrPIMPLE_ != 1))
00187         {
00188             Info<< algorithmName_ << ": not converged within "
00189                 << nCorrPIMPLE_ << " iterations" << endl;
00190         }
00191 
00192         corr_ = 0;
00193         mesh_.data::remove("finalIteration");
00194         return false;
00195     }
00196 
00197     bool completed = false;
00198     if (converged_ || criteriaSatisfied())
00199     {
00200         if (converged_)
00201         {
00202             Info<< algorithmName_ << ": converged in " << corr_ - 1
00203                 << " iterations" << endl;
00204 
00205             mesh_.data::remove("finalIteration");
00206             corr_ = 0;
00207             converged_ = false;
00208 
00209             completed = true;
00210         }
00211         else
00212         {
00213             Info<< algorithmName_ << ": iteration " << corr_ << endl;
00214             storePrevIterFields();
00215 
00216             mesh_.data::add("finalIteration", true);
00217             converged_ = true;
00218         }
00219     }
00220     else
00221     {
00222         if (finalIter())
00223         {
00224             mesh_.data::add("finalIteration", true);
00225         }
00226 
00227         if (corr_ <= nCorrPIMPLE_)
00228         {
00229             if (nCorrPIMPLE_ != 1)
00230             {
00231                 Info<< algorithmName_ << ": iteration " << corr_ << endl;
00232                 storePrevIterFields();
00233             }
00234 
00235             completed = false;
00236         }
00237     }
00238 
00239     return !completed;
00240 }

the first check is done to see if the maximum number of iterations is exceeded

if (corr_ == nCorrPIMPLE_ + 1)

if so,

mesh_.data::remove("finalIteration");

what does it mean?

Then convergence is checked

if (converged_ || criteriaSatisfied())

my question here is, why are there two different indicators of convergence "converged_" and "criteriaSatisfied()"? Where can one provide the criteria to be satisfied? I also looked on the bool Foam:impleControl::criteriaSatisfied(), but it also wasn't easy to understand, what is being done there.

I would really appreciate, if someone takes some time and explains it for such noobs as me.

Best regards,
Illya