  We consider the application of active flow control to modify the radial
pressure distribution of a single-phase wall-normal vortex. The present flow is
based on the Burgers vortex model but with a no-slip boundary condition
prescribed along its symmetry plane. The wall-normal vortex serves as a model
for vortices that emerge upstream of turbomachinaries, such as pumps. This
study characterizes the baseline vortex unsteadiness through numerical
simulation and dynamic mode decomposition. The insights gained from the
baseline flow are used to develop an active flow control technique with
rotating zero-net-mass blowing and suction for the objective of modifying the
core pressure distribution. The effectiveness of the control strategy is
demonstrated by achieving a widened vortex core with increased pressure. Such
change in the flow field weakens the local strength of the wall-normal vortex
core, potentially inhibiting the formation of hollow-core vortices, commonly
encountered in liquids.
