A fully synthetic turbulent boundary condition with a homogeneous vortex distribution

The boundary condition is applied to a DNS simulation of pipe flow at a Reynolds number of 5300, based on pipe diameter, aiming at reaching fully developed conditions at a short distance from the inlet. The results are compared with those using cyclic boundary conditions, and with two DNS results found in the literature. It is shown that a good agreement is reached for the mean velocity profiles five pipe diameters downstream from the inlet. Also the resolved velocity fluctuations at that location are reasonable. It is concluded that the present implementation of the vortex method boundary condition, based on theoretical mean velocity and turbulence profiles, gives an inlet flow that is sufficiently realistic to reach a well-resolved fully developed turbulent pipe flow at five pipe diameters downstream the inlet.