[cccppp]

Hi all,
Recently, I have tried to confirm the turbulence intensity calculation on Fluent by creating a user-defined expression to compute the turbulence intensity as follows:

Turbulence intensity = sqrt(2/3*Turbulence Kinetic Energy)/(Reference Velocity)

Surprisingly, this expression does not return the exact the same value as the one calculated automatically on Fluent. In low-velocity regions, the error is quite small, less than 0.1 %, but in higher speed regions the error can be as high as 2.5 %.


Does someone know how to explain this difference?

Please see the attached picture with the calculations.