Code Overview

At present, PLUTO can solve different systems of conservation laws in 1, 2 or 3 dimensions using Cartesian, cylindrical or spherical coordinates. The four basic physics modules are

  • Classical hydrodynamics (Euler or Navier-Stokes equations, HD);
  • Magnetohydrodynamics (MHD);
  • Special Relativistic hydrodynamics (RHD);
  • Special Relativistic MHD (RMHD);
  • Resistive Relativistic MHD (ResRMHD)
  • Radiation Relativistic Hydrodynamics (RadRMHD)

On top of these, different physical processes or additional modules may be enabled:

  • Non ideal dissipative processes:   Viscosity / Thermal conduction / Resistivity; 
  • Optically thin radiative losses including atomic / molecular cooling;
  • Ionization / recombination chemical reaction network;
  • Different equations of state: Isothermal / Ideal / Synge / general non-constant gamma-law;
  • Fixed gravity; 
  • Shearing box equations;

Equations are discretized and solved on structured meshes supportingStatic or adaptive mesh refinement 

  • Different coordinate systems: Cartesian / Cylindrical Axisymmetric / Polar / Spherical; 
  • Uniform or stretched grids; 

Both serial and massively parallel computations on distributed memory architectures are possible.

Available numerical methods.

Modularity applies not only to the type of equations being solved but also to the capability of enabling different numerical algorithms to be employed and combined in different contexts and different components. 

PLUTO solves the fluid equations by means of shock-capturing Godunov-type methods adopting a conservative discretization based on finite volume or finite difference methods. In this formulation interface fluxes are computed by solving a Riemann problem between left and right interface states. A typical time step cycle consists of a i) an explicit time-marching algorithm, ii) a piece-wise reconstruction scheme, iii) a Riemann solver.

For each step, different options can be indipendently selected from:

  • Time stepping: RK time stepping / Characteristic Tracing / MUSCL-Hancock for hyperbolic PDE;  Super-Time-Stepping / RK-Legendre to speed-up explicit time-stepping for parabolic terms, FARGO scheme for orbital advection of (magnetized) shear flows
  • Reconstruction: 2nd-order slope-limited TVD, PPM, WENO and MP5
  • Riemann Solvers: two-Shocks, Roe, HLLD, HLLC, HLL and Lax-Friedrichs;

In addition, MHD and relativistic MHD are evolved by selecting different strategies to enforce the divergence-free condition, including Constrained transport (CT) / hyperbolic divergence cleaning / Powell's 8 wave formulation.

Please refer to the documentation page for more information.

© PLUTO Team - 2024