Initial Computational Investigation Toward Passive Transition Delay Using a Phononic Subsurface

Abstract

This paper documents progress towards developing a passive transition delay strategy using a phononic subsurface (PSub). A high-order implicit large-eddy simulation (ILES) solver is coupled with a reduced order model of a beam-based PnC which serves as the PSub. Two-dimensional simulations of a flat plate boundary layer at a Reynolds number of 1,081,642 per meter is considered. A disturbance generator in the form of a morphing surface is located at x =0.273 m downstream of the plate leading edge and the PSub with a truncation resonance near the disturbance frequency is embedded in the plate downstream at x = 0.388 m. The PSub response to and effect on flow disturbances is evaluated which results in infinitesimal surface motion, (~10E−6 m), out of phase with the input loading. This effect culminates in a local reduction in perturbation kinetic energy and is in agreement with recent simulations that demonstrated flow stabilization in a channel flow configuration. Prescribed surface motion simulations using a traveling surface wave with an amplitude on the order of 10E−6 m can effectively control disturbance growth. A newly developed linear stability analysis incorporating the PSub model is also presented and validated against the CFD to help guide ongoing flow control efforts.