When performing a Detached-Eddy Simulation (DES) calculation with the Realizable k-epsilon approach, no near-wall treatment can be selected for the flow. In fact, the near-wall flow treatement corresponds to enhanced-wall treatment (EWT), which is described in section “4.16.5. Enhanced Wall Treatment ε-Equation (EWT-ε)” in Fluent Theory Guide: https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v190/flu_th/flu_th_sec_ewt_eps.html?q=enhanced%20wall%20treatment For DES approach, it is also preferable to consider a low-Reynolds grid resolution (y+ ~ 1) so that boundary velocity profile is explicitly recovered by the RANS portion of the DES calculation. Please also note that SDES is more advanced than original DES regarding shielding function. Be advised you can find more information on the different Scale-Resolving Simulations (SRS) approaches such as variants of DES in solution 2023897.