I have atomistic wall.Argon liquid with copper wall.I used LJ model for interaction.and I measured the temperature by variable and fix ave/spatial command (that is in manual).
If you have subtracted out the flow field (e.g. see compute temp/profile), then
the temperature you measure in the fluid is the correct one. I’m not
sure what your question is. A sanity check is to dump the velocities
and calculate the thermal temperature yourself.