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}
}
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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