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In the current work we numerically study the effect of traveling-wave surfacemorphing actuation on the suction surface of NACA0012 at Re = 1,000. Althoughthis actuation strategy has been studied at higher Reynolds numbers for anairfoil and a rectangular flat plate, its effects at low Reynolds numbers havenot yet been investigated. The kinematics of actuation are defined bywavenumber and wavespeed, both of which are varied over a wide range of valuesto include parameters that considerably change the lift dynamics as well asthose that do not. We first study the effect of actuation at an angle of attackof $\alpha$=5{\deg}, where the unactuated flow is steady. The lift dynamics arefound to align with the surface morphing kinematics, and there is alow-pressure minimum shown to be introduced into the flow-field by morphingthat advects at a speed agnostic to the morphing parameters. Lift benefits arefound to be maximal when the morphing kinematics align with this intrinsic flowspeed. We then investigate the role of morphing in the presence of an unsteady,separated baseline flow (with intrinsic vortex-shedding processes) at$\alpha$=15{\deg}. At this higher angle of attack, we identify three distinctbehavioral regimes based on the relationship between morphing and theunderlying shedding frequency. Of these regimes, the most beneficial to meanlift is the lock-on regime, where the vortex-shedding dynamics align with themorphing kinematics. We also identify other regimes where morphing can becomeout of phase with the vortex-shedding dynamics, termed here the interactiveregime, and where morphing leaves the unactuated dynamics unaltered, termedhere the superposition regime. At the higher angle of attack, parametersleading to lift benefits/detriments are explained in terms of the effect ofmorphing on the leading and trailing-edge vortex.

Surface morphing for aerodynamic flows at low and stalled angles of attack