Predefined Variables
This section lists some predefined variables that are available to evaluate heat fluxes, sources, and integral quantities used in heat and energy balance. All the variable names begin with the physics interface name (the prefix). By default the Heat Transfer interface prefix is ht, and the Heat Transfer in Shells interface prefix is htlsh. As an example, you can access the variable named tflux using ht.tflux (as long as the physics interface is named ht).
Table 3-1: Predefined Heat Balance Variables.
Variable
Name
Geometric Entity level
 Global variables
dEiInt
Total Accumulated Heat Rate
Global
ntfluxInt
Total Net Heat Rate
Global
WstrInt
Total Stress Power
Global
heatBalance
Heat Balance
Global
 Domain variables
tflux
Total Heat Flux (Heat Transfer Interface)
Domains
dflux
Conductive Heat Flux (Heat Transfer Interface)
Domains
cflux
Convective Heat Flux (Heat Transfer Interface)
Domains
turbflux
Turbulent Heat Flux (Heat Transfer Interface)
Domains
tflux_u
tflux_d
tflux_z
Total Out-of-Plane Heat Flux (Heat Transfer Interface)
Out-of-plane domains (1D and 2D), boundaries
rflux_u
rflux_d
rflux_z
Radiative Out-of-Plane Heat Flux (Heat Transfer Interface)
Out-of-plane domains (1D and 2D), boundaries
q0_u
q0_d
q0_z
Out-of-Plane Heat Flux (Heat Transfer Interface)
Out-of-plane domains (1D and 2D)
 Boundary variables
ntflux
Normal Total Heat Flux (Heat Transfer Interface)
Boundaries
ndflux
Normal Conductive Heat Flux (Heat Transfer Interface)
Boundaries
ncflux
Normal Convective Heat Flux (Heat Transfer Interface)
Boundaries
rflux
Radiative Heat Flux (Heat Transfer Interface)
Boundaries
q0
Inward Heat Flux (Heat Transfer Interface)
Boundaries
ntflux_u
ntflux_d
Internal normal total heat flux, upside and downside (Internal Boundary Heat Fluxes)
Interior boundaries
ndflux_u
ndflux_d
Internal normal conductive heat flux, upside and downside (Internal Boundary Heat Fluxes)
Interior boundaries
ncflux_u
ncflux_d
Internal normal convective heat flux, upside and downside (Internal Boundary Heat Fluxes)
Interior boundaries
Table 3-2: Predefined Energy Balance Variables.
Variable
Name
Geometric Entity level
 Global variables
dEi0Int
Total Accumulated Energy Rate
Global
ntefluxInt
Total Net Energy Rate
Global
WInt
Total Work Source
Global
energyBalance
Energy Balance
Global
 Domain variables
teflux
Total Energy Flux (Heat Transfer Interface)
Domains
dflux
Conductive Heat Flux (Heat Transfer Interface)
Domains
thflux
Total Enthalpy Flux (Heat Transfer Interface)
Domains
 Boundary variables
nteflux
Normal Total Energy Flux (Heat Transfer Interface)
Boundaries
ndflux
Normal Conductive Heat Flux (Heat Transfer Interface)
Boundaries
nthflux
Normal Total Enthalpy Flux (Heat Transfer Interface)
Boundaries
q0
Inward Heat Flux (Heat Transfer Interface)
Boundaries
nteflux_u
nteflux_d
Internal normal total energy flux, upside and downside (Internal Boundary Energy Fluxes)
Interior boundaries
ndflux_u
ndflux_d
Internal normal conductive heat flux, upside and downside (Internal Boundary Heat Fluxes)
Interior boundaries
nthflux_u
nthflux_d
Internal normal enthalpy flux, upside and downside (Internal Boundary Energy Fluxes)
Interior boundaries
Table 3-3: Predefined Heat Source Variables.
Variable
Name
Geometric Entity level 
 Global variables
QInt
Total Heat Source
Global
 Domain variables
Qtot
Total heat source (Domain Heat Sources)
Domains
 Boundary variables
Qbtot
Total boundary heat source (Boundary Heat Sources)
Boundaries
Qltot
Total line heat source (Line and Point Heat Sources)
Edges, Points (2D, 2D axial symmetry)
Qptot
Point heat source (Line and Point Heat Sources)
Points
Table 3-4: Other Predefined Heat Transfer Variables.
Variable
Name
Geometric Entity level
 Global variables
Tref
Reference temperature
Global
 Domain variables
alpha
Damage indicator (see Theory for Bioheat Transfer)
Domains
alphanecr
Instant tissue necrosis indicator (see Theory for Bioheat Transfer)
Domains
theta_d
Fraction of damage (see Theory for Bioheat Transfer)
Domains
theta_d_sm
Fraction of total damage (see Theory for Bioheat Transfer)
Domains
T_dp
Dew Point Temperature
Domains
T_eq
Equivalent Temperature
Domains
psat
Saturation Pressure
Domains
phi
Relative Humidity
Domains
Lv
Latent Heat of Evaporation
Domains
 Boundary variables
h
Heat transfer coefficient (see Convective Heat Transfer Correlations)
Exterior boundaries
Some of these variables are only available with the Heat Transfer Module (rflux_u, rflux_d, rflux_z, q0_u, q0_d, and q0_z), or when either the CFD Module or the Heat Transfer Module is added (rflux and turbflux).
All the variables in Table 3-1, Table 3-2, and Table 3-3, with the exception of turbflux and Qptot, also exist with the suffix _material, which correspond to the same variables, but evaluated in the material frame. For example, ndflux is the normal conductive heat flux evaluated in the spatial frame, and ndflux_material is the normal conductive heat flux evaluated in the material frame.