Energy Transport

EnergyTransport solves the energy equation in the reactive-flow sub-tree. It handles the fluid and solid thermal properties (heat capacity, density, conductivity, viscosity), the convective scheme, and the optional conjugate-heat-transfer coupling between fluid and solid regions. Sutherland-law coefficients ($TMu0, $SMu0, $Mu0) are read for the temperature-dependent viscosity.

Key Classes and Concepts

• EnergyTransport : public OPObject: per-grid-point temperature evolution for reactive flows.

Usage

Input

Defined in the @EnergyTransport block.

@EnergyTransport

# Fluid (non-reacting mixture) properties {#fluid-non-reacting-mixture-properties}
$Pr                  Prandtl number                     : 0.71
$Cp                  Fluid heat capacity                : 1005.0
$Mw                  Fluid molar weight                 : 0.02896

# Advection scheme (pick one) {#advection-scheme-pick-one-1}
$AdvectionUpwind     Upwind convective scheme           : No
$AdvectionCentral    Central-difference scheme          : No
$AdvectionVanLeer    van Leer limited scheme            : Yes

# Conjugate heat transfer {#conjugate-heat-transfer}
$Conjugate           Solve solid heat transfer too      : No
$Ts0                 Initial solid temperature          : 300.0
$Cps                 Solid heat capacity                : 900.0
$Rhos                Solid density                      : 5000.0
$Ks                  Solid thermal conductivity         : 237
$T0                  Reference (inlet) temperature      : 300.0
$ATstar              Adimensional star-T reference      : 100.0
$TempSolid           Solid temperature (hot side)       : 300.0
$TempSolidCold       Solid temperature (cold side)      : 300.0

# Sutherland law for viscosity {#sutherland-law-for-viscosity}
$TMu0                Reference temperature (Sutherland) : 273.0
$SMu0                Sutherland constant                : 110.5
$Mu0                 Reference viscosity (Pa·s)         : 1.68e-05

$IF_ENERGY           Solve the energy equation          : Yes
$BCOrder             Boundary-condition order           : 0

Output

Temperature field through the standard VTK pipeline. When conjugate heat transfer is enabled, the solid temperature is also written.

Example

#include "ReactiveFlows/EnergyTransport.h"

EnergyTransport ET(OPSettings, InputFile);

for(RTC.tStep = RTC.tStart; RTC.tStep <= RTC.nSteps; RTC.IncrementTimeStep())
{
    // ... flow + species update ...
    ET.Solve(Phi, Mix, BC, RTC.dt);
}

Dependencies

• FlowMixture — global mixture state.
• SpeciesTransport — species concentrations feeding into the mixture energy.
• ThermoChemistry — heat release from reactions.
• BoundaryConditions.