does anyone have any idea why I am getting periodic (that seems to coincide with the inflow time step) damped-oscillation-type background pressure in my results? **Setup**: Forward-facing-step extending up to the outlet and sides **Computational Domain size**: dX, dY, dZ = 30H, 6H, 30H where H is the height of the step. The fetch distance from inlet to the step is 10H **Simulation type**: incompressible LES with turbulent boundary layer inlet **BCs**: inlet: (TBL with

timeVaryingMappedFixedValue

) outlet: inlet/outlet sides:

cyclicAMI

top: slip ground and step surfaces: no-slip **The problem**: The pressure field over the entire domain shows a periodic fluctuations (see attached pictures for the time-histories and spectra taken from a point far above the step avoiding body-generated turbulence). What is the source of this pressure fluctuation? And how do I get rid of it? **Notes**: * This does not occur when the inlet is smooth boundary layer. * The first occurrence in the spectra shifts with inflow time step. * In the absence of the step (i.e., empty domain), the spike in energy disappears