[Dronzer]

Hi everyone,
I am trying to estimate cd and cl for NACA 0012 profile. The Mach number and Reynolds number should be 0.15 and 6 million respctively. I am using far field pressure boundary condition(figure attached) and hence I was able to fix Mach number(leading to a fixed value of velocity at the boundary).
The problem is, how do I fix the Reynolds number for a fixed chord length? I could have adjusted either density or viscosity of air to get the desired Reynolds number as suggested by some of the previous threads in the forum (1.Reynolds Number Calculation in Fluent and effect on results
2.Reynolds number input in fluent). But, I am using ideal gas equation for density and Sutherland law for viscosity which means I can not change them to get my desired Reynolds number.
Does anybody has a clue?
Thanks in advance.

[LuckyTran]

You can't.

Normally fixing the Mach number does not fix the velocity (because pressure and temperature can still change). But presumably you are using some fixed ambient? conditions and so your velocity is also fixed and hence also the Reynolds number because your chord is fixed.

You need to free up some constraints. E.g. the stagnation pressure, the stagnation temperature, etc.

[Dronzer]

Hi LuckyTran,

Thank you so much for the reply.
One more question...
I don't want to use unrealistic ambient conditions and fluid properties in the simulation. So in that case, the only way to get my desired Reynolds number (with already fixed value of Mach number) is to adjust the chord length. Am I correct?

[Cambridge]

Hi, have you got the idea? I need to set conditions as well.

[Dronzer]

Originally Posted by Cambridge

Hi, have you got the idea? I need to set conditions as well.

Hi,

You can adjust the reference pressure or temperature to get the desired Mach and Reynolds number.

[Cambridge]

Hi

Okay, thank you so much for your help. Could you please share any references for naca0012 aerodynamics validation except for nasa?

Sincerely