Solution of phase fraction equation in icoReactingMultiphaseInterFoam
 

Hello everybody,


could anyone explain to me why the phase fraction equation in the OpenFOAMv2112 solver icoReactingMultiphaseInterFoam is being solved twice in the icoReactingMultiphaseInterFoam.C file: once in the runtime loop under fluid.solve() and once again in the pimple loop by including YEqns.H?


I've checked the source files and it seems like both solution methods are extremely similar. In both cases a flux correction is being calculated and limited with MULES. Then the phase fraction equation is solved by calling alpha1Eqn.solve()/YiEqn.solve() and again limited with MULES explicitSolve.


I'd appreciate it, if anyone could help me understand why these calculations are performed twice, I'm probably missing something.



BR
Dennis