Blending Function for Numerics

What are Shielding and Blending functions in SBES model?

When running the SBES model, the "Shielding function for SBES" switches between the RANS (=1) and the LES (=0) region. The "Blending Function for DES model" does not enter into the turbulence model but switches the numerical treatment from Upwind Biased (=1) to Central difference (=0). The name is historic - it should be called "Blending Function for Numerics". The numerics blending is taken over from the DES model (Ansys CFX-Theory documentation: 2.6.4 "Discretization of the Advection Terms).

A closer agreement of the numerics blending to the enhanced model blending of the SBES formulation can be enforced by changing the default value of the model parameter:

C DES for k epsilon Regime = 0 (default is 0.61)

RULES:
SINGLETON: SBES COEFFICIENTS
Solver Name = SBES
Description = Controls blending between LES and RANS for \
SBES turbulence model.
Optional Parameter List = C Shielded DES, \
Csdes, \
C DES for k omega Regime, \
C DES for k epsilon Regime
END
END

FLOW: Flow Analysis
DOMAIN: fluid
FLUID MODELS:
TURBULENCE MODEL:
Option = SBES SST
SBES COEFFICIENTS:
C DES for k epsilon Regime = 0
END
END
END
END
END