# Spectral energy cascade in thermoacoustic shock waves

@article{Gupta2017SpectralEC,
title={Spectral energy cascade in thermoacoustic shock waves},
author={Prateek Gupta and Guido Lodato and Carlo Scalo},
journal={Journal of Fluid Mechanics},
year={2017},
volume={831},
pages={358 - 393}
}
• Published 27 January 2017
• Physics, Engineering
• Journal of Fluid Mechanics
We have investigated thermoacoustically amplified quasi-planar nonlinear waves driven to the limit of shock-wave formation in a variable-area looped resonator geometrically optimized to maximize the growth rate of the quasi-travelling-wave second harmonic. Optimal conditions result in velocity leading pressure by approximately $40^{\circ }$ in the thermoacoustic core and not in pure travelling-wave phasing. High-order unstructured fully compressible Navier–Stokes simulations reveal three…
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