Helium diffusion into CO2 plume
I am running toughreact V3 example problem 5 with diffusion switched on and helium added to the fluid and CO2 phase. During and after CO2 injection i expect the helium to diffuse into the CO2 due to higher solubility, however, the helium concentration drops to very very low concentration in the gas and fluid phase in the grid blocks with CO2. I am not sure why this is happening. Any help is much appreciated.
Thanks and best wishes
just two guesses: trace gases can be written in the output in different units (I think partial pressure, mole fraction) which has to be chosen by igasflag in solute.inp record 7. Sometimes these units may be a little confusing, especially since the manual concerning igasflag has not been updated from V2. I once stumbled about this topic, maybe it has been corrected meanwhile.
Second guess: Maybe your initial He concentration in the fluid is too small compared to the equilibrium solubility. Have you tried increasing initial He(aq) concentration?