Have you also used mixture velocity of propane-air mixture along side mean viscosity?

Hello Mr Rohit singh Gulia , I used the mixture velocity to calculate reynolds ( Re= axial_velocity*dh/Kinematic viscosity) but for the kinematic_viscosity just I interpolates it between two Temperature degree...

Is this method correct?

I think you should also factor in the volume/mass fraction of the components. Say, c represents the fraction of air, then 1-c is fraction of propane. The net viscosity could then by = c*mu_air + (1-c)*mu_propane.

hello sir Chitrarth Lav I tried to do that but he still doesn't work..

I get a Reynolds value less than what I looking for, I don't know what's the mistak I do...any suggestion sir?