In the following we describe the session file configuration. Specifically we consider the sections
under the tag <CONDITIONS> in the session (.xml) file.
Under this section it is possible to set the parameters of the simulation.
TimeStep is the time-step we want to use;
FinTime is the final physical time at which we want our simulation to stop;
NumSteps is the equivalent of FinTime but instead of specifying the physical final
time we specify the number of time-steps;
IO_CheckSteps sets the number of steps between successive checkpoint files;
IO_InfoSteps sets the number of steps between successive info stats are printed
to screen;
Gamma ratio of the specific heats. Default value = 1.4;
pInf farfield pressure (i.e. p∞). Default value = 101325 Pa;
rhoInf farfield density (i.e. ρ∞). Default value = 1.225 Kg∕m3;
TInf farfield temperature (i.e. T∞). Default value = 288.15 K;
Twall temperature at the wall when isothermal boundary conditions are employed
(i.e. Tw). Default value = 300.15K;
uint farfield X-component of the velocity (i.e. u∞). Default value = 0.1 m∕s;
vInf farfield Y -component of the velocity (i.e. v∞). Default value = 0.0 m∕s;
wInf farfield Z-component of the velocity (i.e. w∞). Default value = 0.0 m∕s;
mu dynamic viscosity (i.e. μ∞). Default value = 1.78e-05 Pas;
Pr Prandtl number. Default value = 0.72;
thermalConductivity thermal conductivity (i.e. κ∞). This can be set as an
alternative to Pr, in which case the Prandtl number is calculated from κ∞ (it is
only possible to set one of them). By default, this is obtained from the Prandtl
number;
Under this section it is possible to set the solver information.
EQType is the tag which specify the equations we want solve:
NavierStokesCFE (Compressible Navier-Stokes equations);
EulerCFE (Compressible Euler equations).
IsentropicVortex (Isentropic vortex test case).
RinglebFlow (Ringleb flow test case).Projection is the type of projection we want to use:
DisContinuous.AdvectionType is the advection operator we want to use:
WeakDG (classical DG in weak form);
FRDG (Flux-Reconstruction recovering nodal DG scheme);
FRSD (Flux-Reconstruction recovering a spectral difference (SD) scheme);
FRHU (Flux-Reconstruction recovering Huynh (G2) scheme);
FRcmin (Flux-Reconstruction with c = cmin);
FRcinf (Flux-Reconstruction with c = ∞).DiffusionType is the diffusion operator we want to use for the Navier-Stokes
equations:
LDGNS (LDG);
LFRDGNS (Flux-Reconstruction recovering nodal DG scheme);
LFRSDNS (Flux-Reconstruction recovering a spectral difference (SD) scheme);
LFRHUNS (Flux-Reconstruction recovering Huynh (G2) scheme);
LFRcminNS (Flux-Reconstruction with c = cmin);
LFRcinfNS (Flux-Reconstruction with c = ∞).TimeIntegrationMethod is the time-integration scheme we want to use. Note that only
an explicit discretisation is supported:
ForwardEuler;
RungeKutta2_ImprovedEuler;
ClassicalRungeKutta4.UpwindType is the numerical interface flux (i.e. Riemann solver) we want to use for the
advection operator:
AUSM0;
AUSM1;
AUSM2;
AUSM3;
Average;
ExactToro;
HLL;
HLLC;
LaxFriedrichs;
Roe.ViscosityType is the viscosity type we want to use:
Constant (Constant viscosity);
Variable (Variable viscosity through the Sutherland’s law.);
In this section we can specify the boundary conditions for our problem. First we need
to define the variables under the section VARIABLES. For a 1D problem we have:
For a 2D problem we have
For a 3D problem we have:
After having defined the variables depending on the dimensions of the problem we want to solve it is necessary to specify the boundary regions on which we want to define the boundary conditions:
Finally we can specify the boundary conditions on the regions specified under BOUNDARYREGIONS.
In the following some examples for a 2D problem:
Under the two following sections it is possible to define the initial conditions and the exact solution (if existent).