Numerical Analysis of Porous Coatings Stabilizing Capabilities on Hypersonic Boundary-Layer Transition

Numerical Optimization of Porous Coatings Stabilizing Capabilities on Hypersonic Boundary-Layer Transition

“…The wall impedance discontinuity at x = 0.25, captured by the DNS only, appears to have a limited effect on the perturbations. Additionally, the history effects produced by the UAC on the development of the Mack's second mode, which are not captured by the LST, have no significant impact in the present case contrary to what was observed in [8].…”

“…This is an indication that the slower-propagating frequencies correspond to the highfrequency components, whereas the faster-propagating frequencies are the lower-frequency ones. This observation is consistent with the findings reported by Fiévet et al [8]. Furthermore, the UAC demonstrates again its ability to absorb the acoustic energy of Mack's second mode.…”

“…A potential way to examine the impact of macroscopic properties of material with random microstructure is the use of high-fidelity numerical simulations in which the acoustic response of the porous material is modeled. Indeed, recent advancements in the mathematical modeling of acoustic metasurfaces have been emphasized [17] [8]. The use of a mathematical impedance model of acoustic metasurfaces as a boundary condition in a DNS can be employed to optimize the microstructure of the metasurface to attain specific acoustic properties.…”