On this website (https://www.cfd-online.com/Tools/turbulence.php), estimates of turbulent quantities are established from the setting of turbulence intensity and turbulence length scale. Right there it is explained that the indication of the turbulence length scale can vary according to the software.
The most orientative indication that I found in the documentation of CS is the following (for the variable almax, which corresponds to the turbulence length scale as far as I know):
What are the detailed guidelines to take into account to set this value in code_saturne?[...] Assign a value of the order of the largest dimension of the physical domain in which the flow may develop. [...]
If I am simulating external flow around an airfoil or a vehicle, should this length be the length of the airfoil and the length of the vehicle?