Reliability of wall shear stress estimations of the flow around a wall-mounted cylinder

We demonstrate that the flow structure and predicted wall shear stresses strongly depend on the inflow condition, which has to take into account turbulent fluctuations and the secondary flow, if present. A maximum amplification factor of the time-averaged wall shear stress of 12.0 with respect to the one in the oncoming flow field shows up in the lateral front of the cylinder. Instantaneous wall shear stresses however reach a maximum amplification factor of up to 40 in the wake of the cylinder.