Examples » RieCG: Diesel engine

This example uses RieCG in Inciter to compute the time-evolution of a flow inside a single cylinder of a Diesel engine.

Problem setup

The problem is initialized by prescribing a pressure-difference between the inflow and outflow. Symmetry (free-slip) conditions are prescribed on all internal walls. Below is a rendering of the mesh used. Inflow is at the bottom, outflow is at the top.

Image

Code revision to reproduce

To reproduce the results below, use code revision c9706cb and the control file below.

Control file

-- vim: filetype=lua:

print "Diesel engine cylinder"
-- mesh: diesel_ssm.exo

-- nstep = 50
term = 0.005
cfl = 0.5
ttyi = 10

part = "rcb"

mat = { spec_heat_ratio = 1.4 }

ic = {
  density = 1.1996, -- kg/m^3
  velocity = { 0.0, 0.0, 0.0 },
  -- ic pressure = (p_in + p_out) / 2, Pa
  pressure = 93850 -- case A
  -- pressure = 95200 -- case B
  -- pressure = 95850 -- case C
  -- pressure = 96500 -- case D
}

bc_sym = {
  sideset = { 3 }
}

bc_pre = {
  inlet = {
    density = 1.996,
    pressure = 1.005e5,
    sideset = { 2 }
  },
  outlet = {
    density = 1.1996,
    pressure = 87200, -- case A
    -- pressure 89900, -- case B
    -- pressure 91200, -- case C
    -- pressure 92500, -- case D
    sideset = { 1 }
  }
}

fieldout = {
  iter = 100
}

histout = {
  -- iter = 1,
  -- time = 4.0e-3,
  range = { 15.0, 20.0, 1.0e-5 },
  points = {
    { 0.5, 2.001, 0.0 },
    { 5.5, 2.001, 0.0 }
  }
}

diag = {
  iter = 10,
  format = "scientific",
  precision = 6
}

integout = {
  iter = 10,
  -- time = 4.0e-3,
  -- range ={ 15.0, 20.0, 1.0e-5 },
  sideset = { 1, 2 },
  format = scientific
}

Run on 32 CPUs

./charmrun +p32 Main/inciter -i diesel_ssm.exo -c diesel.q

Visualization

ParaView can be used for interactive visualization of the numerically computed 3D fields as

paraview out.e-s.0.32.0

The fluid pressure at an instant in time is plotted below.

Image