32        using VolumeVariables = 
typename OutputModule::VolumeVariables;
 
   33        using FluidSystem = 
typename VolumeVariables::FluidSystem;
 
   36        for (
int compIdx = 0; compIdx < VolumeVariables::numFluidComponents(); ++compIdx)
 
   38            out.addVolumeVariable([compIdx](
const auto& v){ 
return v.moleFraction(0, compIdx); },
 
   39                                  "x^" + FluidSystem::componentName(compIdx));
 
   40            out.addVolumeVariable([compIdx](
const auto& v){ 
return v.massFraction(0, compIdx); },
 
   41                                  "X^" + FluidSystem::componentName(compIdx));
 
   43        out.addVolumeVariable( [](
const auto& v){ 
return v.density(); }, 
IOName::density());