scalar CoNum = -GREAT;

forAll(fluidRegions, regionI)
{
  CoNum = max
          (
              compressibleCourantNo
              (
                  fluidRegions[regionI],
                  runTime,
                  rhoFluid[regionI],
                  phiFluid[regionI]
              ),
              CoNum
          );
}
/*
    forAll(porousFluidRegions, porousI)
    {
        CoNum = max
        (
            compressibleCourantNo
            (
                porousFluidRegions[porousI],
                runTime,
                rhoPorous[porousI],
                phiPorous[porousI]
            ),
            CoNum
        );
    }
*/