Examples » Inciter: Example set up for the four material gas impact problem

This example runs the Multi-material DG hydrodynamics algorithm for the four material gas impact problem from Pandare et al. (Comp. Fluids 2021). It uses a second-order finite volume method for spatial discretization, with THINC material interface reconstruction. The problem is configured using the user-defined problem class with box-type initial conditions, and symmetric boundary conditions on all domain boundaries. For further details about the numerical method see Pandare et al. (Comp. Fluids 2021)

Image Initial conditions

Control file

# vim: filetype=sh:
# This is a comment
# Keywords are case-sensitive

title "Gas impacting two slabs problem"

inciter

  term 10.0
  cfl 0.75
  ttyi 25  # TTY output interval
  scheme p0p1
  limiter vertexbasedp1

  partitioning
    algorithm mj
  end

  multimat

    physics veleq
    depvar u

    prelax 1  # finite-rate pressure relaxation
    prelax_timescale 0.1  # time scale for pressure relaxation

    intsharp 1  # THINC interface reconstruction
    intsharp_param 2.5  # interface steepness parameter

    nmat 4
    material
      gamma 50 1.66666667 1.249 1.4 end  # ratio of specific heats
      cv 0.32539682 28.7 200.0 717.5 end  # specific heats at constant volume
      pstiff 0.0 0.0 0.0 0.0 end  # stiffness parameter
    end

    ic
      # background
      materialid 4 end
      pressure 1.0 end
      temperature 0.0034843206 end
      velocity 0.0 0.0 0.0 end

      # slab-1
      box
        materialid 2
        xmin 1.0 xmax 1.1
        ymin -0.5 ymax 2.0
        zmin -1.0 zmax 1.0
        pressure 1.0
        temperature 0.0034843206
      end

      # slab-2
      box
        materialid 3
        xmin 1.1 xmax 1.3
        ymin -0.5 ymax 2.0
        zmin -1.0 zmax 1.0
        pressure 1.0
        temperature 0.0034843206
      end

      # impactor
      box
        materialid 1
        xmin 0.25 xmax 0.75
        ymin -0.5 ymax 1.1
        zmin -1.0 zmax 1.0
        pressure 2.0
        temperature 0.0062717771
        velocity 0.2 0.0 0.0 end
      end
    end

    bc_sym
      sideset 1 2 3 4 5 6 end
    end

  end

  diagnostics
    interval 250
    format scientific
    error l2
  end

  field_output
    interval 2500
    var elem
      material_indicator  # material indicator function
      density  # bulk density
      pressure  # bulk pressure
      specific_total_energy  # bulk specific total energy
      x-velocity  # bulk x-velocity
      y-velocity  # bulk y-velocity
      z-velocity  # bulk z-velocity
    end
  end

end

Example run on 16 CPUs

./charmrun +p16 Main/inciter -c mmimpact4mat.q -i gasimpacthalf_ss6_struc24k.exo -v

Setup screen output

                                   < FACTORY >                                  
                                   ---- o ----                            

 * Unknowns data layout (CMake: FIELD_DATA_LAYOUT):
 --------------------------------------------------
     unknown-major                           

 * PDE factory legend, policy codes:
 -----------------------------------
     Physics configuration (policy code: p)
        A - Advection
        D - Advection + diffusion
        E - Euler
        N - Navier-Stokes
        V - Velocity equilibrium
     Test problem (policy code: t)
        U - User-defined
        S - Shear-diffusion
        V - Vortical flow
        N - Nonlinear energy growth
        R - Rayleigh-Taylor
        T - Taylor-Green
        Z - Zalesak's slotted cylinder
        G - Advection of 2D Gaussian hump
        C - Advection of cylinder
        X - Deformation of cylinder in a vortex
        F - Shedding flow over triangular wedge
        H - Sod shock-tube
        O - Rotated Sod shock-tube
        B - Sedov blast-wave
        I - Interface advection
        A - Advection of 2D Gaussian hump for Euler equations
        W - Water-air shock-tube
        E - Shock He-bubble problem
        D - Underwater explosion problem

 * Registered PDEs using continuous Galerkin (CG) methods:
 ---------------------------------------------------------
     Unique equation types                    : 2
     With all policy combinations             : 30
     Compressible single-material flow        : p:EN, t:ABFHNORTUV
     Transport                                : p:AD, t:CGSXZ

 * Registered PDEs using discontinuous Galerkin (DG) methods:
 ------------------------------------------------------------
     Unique equation types                    : 3
     With all policy combinations             : 21
     Compressible multi-material flow         : p:V, t:DEHIUW
     Compressible single-material flow        : p:E, t:ABFHNORTUV
     Transport                                : p:A, t:CGSXZ


                                   < PROBLEM >                                  
                                   ---- o ----                            

 * Title: Gas impacting two slabs problem 
 -----------------------------------------

 * Discretization parameters:
 ----------------------------
     Discretization scheme                    : P0P1+RK
     Limiter function                         : VERTEXBASEDP1
     PE-locality mesh reordering              : false
     Operator-access mesh reordering          : false
     Local time stepping                      : false
     Number of time steps                     : 18446744073709551615
     Start time                               : 0
     Terminate time                           : 10
     CFL coefficient                          : 0.75

 * Partial differential equations integrated (0):
 ------------------------------------------------
   < Compressible multi-material flow >
     dependent variable                       : u
     physics                                  : Velocity equilibrium
     problem                                  : User-defined
     flux                                     : AUSM
     number of materials                      : 4
     finite pressure relaxation               : 1
     pressure relaxation time-scale           : 0.100000
     interface sharpening                     : 1
     interface sharpening parameter           : 2.500000
     number of components                     : 15
     start offset in unknowns array           : 0
     ratio of specific heats                  : { 50 1.66667 1.249 1.4 }
     specific heat at constant volume         : { 0.325397 28.7 200 717.5 }
     material stiffness                       : { 0 0 0 0 }
     IC background material id                : 4
     IC background velocity                   : { 0 0 0 }
     IC background pressure                   : 1
     IC background temperature                : 0.00348432
     IC box 0                                 : { 1 1.1 -0.5 2 -1 1 }
     IC box 0 material id                     : 2
     IC box 0 density                         : 0
     IC box 0 velocity                        : { }
     IC box 0 pressure                        : 1
     IC box 0 internal energy per unit mass   : 0
     IC box 0 mass                            : 0
     IC box 0 internal energy per unit volume : 0
     IC box 0 temperature                     : 0.00348432
     IC box 1                                 : { 1.1 1.3 -0.5 2 -1 1 }
     IC box 1 material id                     : 3
     IC box 1 density                         : 0
     IC box 1 velocity                        : { }
     IC box 1 pressure                        : 1
     IC box 1 internal energy per unit mass   : 0
     IC box 1 mass                            : 0
     IC box 1 internal energy per unit volume : 0
     IC box 1 temperature                     : 0.00348432
     IC box 2                                 : { 0.25 0.75 -0.5 1.1 -1 1 }
     IC box 2 material id                     : 1
     IC box 2 density                         : 0
     IC box 2 velocity                        : { 0.2 0 0 }
     IC box 2 pressure                        : 2
     IC box 2 internal energy per unit mass   : 0
     IC box 2 mass                            : 0
     IC box 2 internal energy per unit volume : 0
     IC box 2 temperature                     : 0.00627178

 * Input/Output filenames and directories:
 -----------------------------------------
     Input mesh(es)                           : { gasimpacthalf_ss6_struc24k.exo }
     Volume field output file(s)              : out.e-s.<meshid>.<numchares>.<chareid>
     Surface field output file(s)             : out-surf.<surfid>.e-s.<meshid>.<numchares>.<chareid>
     History output file(s)                   : out.hist.{pointid}
     Diagnostics file                         : diag
     Checkpoint/restart directory             : restart/

 * Output intervals:
 -------------------
     TTY                                      : 25
     Field and surface                        : 2500
     Diagnostics                              : 250
     Checkpoint/restart                       : 1000

 * Output fields:
 ----------------
     Elem field(s)                            : { density material_indicator pressure specific_total_energy x-velocity y-velocity z-velocity }

Solution contours

Bulk density (top-half) and material indicator (bottom-half) contours for the four material gas impact test:

Image t = 2.0
Image t = 5.5
Image t = 8.5