Gas Viscosity for reacting flow where species will change

MFiX
#1

Just need to confirm this:
It seems that MFiX is calculating the gas viscosity using Sutherland’s law with AIR as a reference. This means in reacting flow where gas species will change, the user must define their own UDF for viscosity calculation.
Thanks.

#2

pretty sure that’s correct, maybe @galvinj can confirm

#3

Yes that is correct - it is air. You could directly modify calc_mu_g.f -> calc_default_mug or you could work through the user hooks. In case of the latter you would need to modify usr_properties.f -> usr_prop_mug. You would also need to include the following in your input file: call_usr=.t. and usr_mug = .t.