Fundamental differences between SPH and grid methods

  title={Fundamental differences between SPH and grid methods},
  author={Oscar Agertz and Ben Moore and Joachim Gerhard Stadel and Doug Potter and Francesco Miniati and Justin I Read and Lucio Mayer and Artur Gawryszczak and Andrey V. Kravtsov and Joseph John Monaghan and {\AA}ke Nordlund and Frazer R. Pearce and V. Quilis and Douglas H. Rudd and Volker Springel and James M. Stone and Elizabeth J. Tasker and R. Teyssier and James Wadsley and Rolf Walder},
  journal={Monthly Notices of the Royal Astronomical Society},
We have carried out a comparison study of hydrodynamical codes by investigating their performance in modelling interacting multiphase fluids. The two commonly used techniques of grid and smoothed particle hydrodynamics (SPH) show striking differences in their ability to model processes that are fundamentally important across many areas of astrophysics. Whilst Eulerian grid based methods are able to resolve and treat important dynamical instabilities, such as Kelvin-Helmholtz or Rayleigh-Taylor… 
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