Inaccuracy of Spatial Derivatives in Riemann Solver Simulations of Supersonic Turbulence

@article{Pan2019InaccuracyOS,
  title={Inaccuracy of Spatial Derivatives in Riemann Solver Simulations of Supersonic Turbulence},
  author={Liubin Pan and Paolo Padoan and {\AA}ke Nordlund},
  journal={The Astrophysical Journal},
  year={2019},
  volume={876}
}
We examine the accuracy of spatial derivatives computed from numerical simulations of supersonic turbulence. Two sets of simulations, carried out using a finite-volume code that evolves the hydrodynamic equations with an approximate Riemann solver and a finite-difference code that solves the Navier–Stokes (N–S) equations, are tested against a number of criteria based on the continuity equation, including exact results at statistically steady state. We find that the spatial derivatives in the N… 

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