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27 changes: 18 additions & 9 deletions Manuals/FDS_User_Guide/FDS_User_Guide.tex
Original file line number Diff line number Diff line change
Expand Up @@ -2434,23 +2434,32 @@ \subsection{Walls with Different Materials Front and Back}
\subsection{Specified Internal Heat Source}

\label{info:INTERNAL_HEAT_SOURCE}
\label{internal_heating}

The condensed phase heat conduction equation has a source term that describes the internal sources and sinks of energy.
There are three types of sources that contribute to this term:
heats of reaction for the pyrolysis (see Sec.~\ref{info:solid_pyrolysis}),
internal absorption and emission of radiation (see Sec.~\ref{info:liquid_fuels}), and the source specified by the user.
An example of the case where specified heat source could be needed is the heating of electrical cables due to internal current.

The internal source term for each layer of the surface is specified using \ct{INTERNAL_HEAT_SOURCE} on the \ct{SURF} line. Its units are \unit{kW/m^3} and the default value is zero. An optional time ramp can be specified for each layer's heat source using \ct{RAMP_IHS}. In the example below, the cylindrical surface describing a cable consists of an outer plastic layer and inner core of metal. The metal core is heated with a power of 300~\unit{kW/m^3}.
The internal source term for each layer of the surface is specified using \ct{INTERNAL_HEAT_SOURCE} on the \ct{SURF} line. Its units are \unit{kW/m^3} and the default value is zero. An optional time ramp can be specified for each layer's heat source using \ct{RAMP_IHS}. In the example below, the cylindrical surface describing a 10~cm long cable segment consists of an outer plastic layer and inner core of metal. The metal core is heated with a power of 300~\unit{kW/m^3}.
\begin{lstlisting}
&SURF ID = 'Cable'
THICKNESS = 0.002,0.008
MATL_ID(1,1) = 'PLASTIC'
MATL_ID(2,1) = 'METAL'
GEOMETRY = 'CYLINDRICAL'
LENGTH = 0.1
INTERNAL_HEAT_SOURCE = 0.,300. /
&SURF ID = 'Cable'
THICKNESS = 0.002,0.008
MATL_ID(1,1) = 'PLASTIC'
MATL_ID(2,1) = 'METAL'
GEOMETRY = 'CYLINDRICAL'
LENGTH = 0.1
INTERNAL_HEAT_SOURCE = 0.,300. /
\end{lstlisting}
Figure~\ref{fig:internal_heating} displays the heat generated by 10 of these cable segments. The exact value is 300~\unit{kW/m^3} multiplied by the volume of the metal within the cable segment, $2 \times 10^{-5}$~\unit{m^3}, multiplied by the number of segments, 10, which equals approximately 0.06~kW.
\begin{figure}[!ht]
\centering
\includegraphics[height=2.35in]{SCRIPT_FIGURES/internal_heating}
\caption[Results of the \ct{internal_heating} test case]{Heating rate of a set of 10 cable segments. The dashed line represents the heat generated by the cable and the dotted line the heat flowing out of the computational domain.}
\label{fig:internal_heating}
\end{figure}


\subsection{Non-Planar Walls and Targets}

Expand Down Expand Up @@ -13531,7 +13540,7 @@ \section{\texorpdfstring{{\tt SURF}}{SURF} (Surface Properties)}
\ct{INIT_IDS} & Char.~Array & Section~\ref{info:trees} & & \\ \hline
\ct{INIT_PER_AREA} & Real & Section~\ref{info:trees} & m$^{-2}$ & \\ \hline
\ct{INNER_RADIUS} & Real & Section~\ref{info:PART_GEOMETRY} & m & \\ \hline
\ct{INTERNAL_HEAT_SOURCE} & Real Array & Section~\ref{info:INTERNAL_HEAT_SOURCE} & \unit{kW/m^3} & \\ \hline
\ct{INTERNAL_HEAT_SOURCE} & Real Array & Section~\ref{info:INTERNAL_HEAT_SOURCE} & \unit{kW/m^3} & 0 \\ \hline
\ct{LAYER_DIVIDE} & Real & Section~\ref{info:LAYER_DIVIDE} & & \ct{N_LAYERS}/2 \\ \hline
\ct{LEAK_PATH} & Int.~Pair & Section~\ref{info:Leaks} & & \\ \hline
\ct{LEAK_PATH_ID} & Character~Pair & Section~\ref{info:Leaks} & & \\ \hline
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2 changes: 2 additions & 0 deletions Utilities/Python/FDS_verification_dataplot_inputs.csv
Original file line number Diff line number Diff line change
Expand Up @@ -452,6 +452,8 @@ d,init_overlap,Miscellaneous/init_overlap_git.txt,Miscellaneous/init_overlap.csv
d,insulated_steel_pipe,Heat_Transfer/insulated_steel_pipe_git.txt,Heat_Transfer/insulated_steel_pipe.csv,1,2,Radius,Temp,Analytical (Temp),k-,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Heat_Transfer/insulated_steel_pipe_prof_1.csv,2,3,Radius,Temperature,FDS (Temperature),ko,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Temperature (insulated_steel_pipe),Radius (m),Temperature (°C),0.01,0.06,1,0,500,1,no,0.05 0.90,SouthEast,,1,linear,FDS_Verification_Guide/SCRIPT_FIGURES/insulated_steel_pipe,Relative Error,end,0.01,Heat Transfer,r^,r,TeX
d,insulated_steel_pipe,Heat_Transfer/insulated_steel_pipe_2d_git.txt,Heat_Transfer/insulated_steel_pipe_2d.csv,1,2,Radius,Temp,Analytical (Temp),k-,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Heat_Transfer/insulated_steel_pipe_2d_prof_2.csv,2,3,Radius,T_in,FDS (Temperature),ko,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Temperature (insulated_steel_pipe_2d),Radius (m),Temperature (°C),0.01,0.06,1,0,500,1,no,0.05 0.90,SouthEast,,1,linear,FDS_Verification_Guide/SCRIPT_FIGURES/insulated_steel_pipe_2d,Relative Error,end,0.01,Heat Transfer,r^,r,TeX
d,insulated_steel_plate,Heat_Transfer/insulated_steel_plate_git.txt,Heat_Transfer/insulated_steel_plate.csv,1,2,Depth,Temp,Analytical (Temp),k-,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Heat_Transfer/insulated_steel_plate_prof_1.csv,2,3,Depth,Temperature,FDS (Temperature),ko,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Temperature (insulated_steel_plate),Depth (m),Temperature (°C),0,0.05,1,0,500,1,no,0.05 0.90,SouthEast,,1,linear,FDS_Verification_Guide/SCRIPT_FIGURES/insulated_steel_plate,Relative Error,end,0.01,Heat Transfer,r^,r,TeX
d,internal_heating,Heat_Transfer/internal_heating_git.txt,Heat_Transfer/internal_heating.csv,1,3,Time,HF,Analytical (HF),k-,0,100000,,400,600,-1.00E+09,1.00E+09,0,Heat_Transfer/internal_heating_devc.csv,2,3,Time,HF_1,FDS (HF_1),k--,0,100000,,400,600,-1.00E+09,1.00E+09,0,Heat Flow (internal_heating),Time (min),Heat Flow (kW),0,10.,60,0,0.08,1,no,0.05 0.90,SouthEast,,1,linear,FDS_User_Guide/SCRIPT_FIGURES/internal_heating,Relative Error,mean,0.01,Heat Transfer,r^,r,TeX
f,internal_heating,Heat_Transfer/internal_heating_git.txt,Heat_Transfer/internal_heating.csv,1,3,Time,HF,blank,blank,0,100000,,400,600,-1.00E+09,1.00E+09,0,Heat_Transfer/internal_heating_devc.csv,2,3,Time,HF_2,FDS (HF_2),k:,0,100000,,400,600,-1.00E+09,1.00E+09,0,Heat Flow (internal_heating),Time (s),Heat Flow (kW),0,10.,60,0,0.08,1,no,0.05 0.90,SouthEast,,1,linear,FDS_User_Guide/SCRIPT_FIGURES/internal_heating,Relative Error,mean,0.01,Heat Transfer,r^,r,TeX
d,isentropic,Pressure_Effects/isentropic_git.txt,Pressure_Effects/isentropic.csv,1,2,Time,Density_1|Density_2,Exact (Density_1)|Exact (Density_2),ko|ro,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Pressure_Effects/isentropic_devc.csv,2,3,Time,density_1|density_2,FDS (density_1)|FDS (density_2),k-|r-,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Density (isentropic),Time (s),Density (kg/m³),0,60,1,1.1,1.4,1,no,0.05 0.90,SouthEast,,1,linear,FDS_Verification_Guide/SCRIPT_FIGURES/isentropic_density,Relative Error,end,0.01,Pressure Effects,kd,k,TeX
d,isentropic,Pressure_Effects/isentropic_git.txt,Pressure_Effects/isentropic.csv,1,2,Time,Pressure_1|Pressure_2,Exact (Pressure_1)|Exact (Pressure_2),ko|ro,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Pressure_Effects/isentropic_devc.csv,2,3,Time,pressure_1|pressure_2,FDS (pressure_1)|FDS (pressure_2),k-|r-,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Pressure (isentropic),Time (s),Pressure (Pa),0,60,1,0,25000,1,no,0.05 0.90,SouthEast,,1,linear,FDS_Verification_Guide/SCRIPT_FIGURES/isentropic_pressure,Relative Error,end,0.01,Pressure Effects,k+,k,TeX
d,isentropic,Pressure_Effects/isentropic_git.txt,Pressure_Effects/isentropic.csv,1,2,Time,Temperature_1|Temperature_2,Exact (Temperature_1)|Exact (Temperature_2),ko|ro,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Pressure_Effects/isentropic_devc.csv,2,3,Time,temperature_1|temperature_2,FDS (temperature_1)|FDS (temperature_2),k-|r-,0,100000,,0,100000,-1.00E+09,1.00E+09,0,Temperature (isentropic),Time (s),Temperature (°C),0,60,1,15,40,1,no,0.05 0.90,SouthEast,,1,linear,FDS_Verification_Guide/SCRIPT_FIGURES/isentropic_temperature,Relative Error,end,0.01,Pressure Effects,k+,k,TeX
Expand Down
1 change: 1 addition & 0 deletions Verification/FDS_Cases.sh
Original file line number Diff line number Diff line change
Expand Up @@ -324,6 +324,7 @@ $QFDS -d Heat_Transfer ht3d_slab.fds
$QFDS -d Heat_Transfer ht3d_sphere_24.fds
$QFDS -p 4 -d Heat_Transfer ht3d_sphere_48.fds
$QFDS -p 64 -d Heat_Transfer ht3d_sphere_96.fds
$QFDS -d Heat_Transfer internal_heating.fds
$QFDS -d Heat_Transfer back_wall.fds
$QFDS -p 4 -d Heat_Transfer back_wall_test.fds
$QFDS -p 3 -d Heat_Transfer back_wall_test_2.fds
Expand Down
4 changes: 4 additions & 0 deletions Verification/Heat_Transfer/internal_heating.csv
Original file line number Diff line number Diff line change
@@ -0,0 +1,4 @@
Time,HF
s,kW
400,0.0603
600,0.0603
54 changes: 54 additions & 0 deletions Verification/Heat_Transfer/internal_heating.fds
Original file line number Diff line number Diff line change
@@ -0,0 +1,54 @@
&HEAD CHID='internal_heating', TITLE='Test INTERNAL_HEAT_SOURCE' /

&MESH IJK=25,25,25, XB=-0.25, 0.25,-0.25, 0.25,0.00,0.50 /

&TIME T_END=600. /

&RADI RADIATION=F /

&SURF ID = 'Cable'
THICKNESS = 0.002,0.008
MATL_ID(1,1) = 'PLASTIC'
MATL_ID(2,1) = 'METAL'
GEOMETRY = 'CYLINDRICAL'
LENGTH = 0.1
INTERNAL_HEAT_SOURCE = 0.,300. /

&MATL ID = 'PLASTIC'
CONDUCTIVITY = 0.1
SPECIFIC_HEAT = 0.05
DENSITY = 100. /

&MATL ID = 'METAL'
CONDUCTIVITY = 50.
SPECIFIC_HEAT = 0.1
DENSITY = 2000. /

&PART ID='Cable Segment', SURF_ID='Cable', STATIC=.TRUE., SAMPLING_FACTOR=1,
PROP_ID='Segment Image', QUANTITIES='PARTICLE TEMPERATURE' /

&PROP ID='Segment Image', SMOKEVIEW_ID='tube', SMOKEVIEW_PARAMETERS='L=0.1','D=0.01','RANDXYZ=1' /

&INIT N_PARTICLES=10, PART_ID='Cable Segment', XB=-0.15,0.15,-0.15,0.15,0.1,0.4 /

&VENT MB='XMIN', SURF_ID='OPEN' /
&VENT MB='XMAX', SURF_ID='OPEN' /
&VENT MB='YMIN', SURF_ID='OPEN' /
&VENT MB='YMAX', SURF_ID='OPEN' /
&VENT MB='ZMIN', SURF_ID='OPEN' /
&VENT MB='ZMAX', SURF_ID='OPEN' /

&DUMP DT_HRR=10, DT_DEVC=10 /

&BNDF QUANTITY='GAUGE HEAT FLUX', CELL_CENTERED=T /
&BNDF QUANTITY='WALL TEMPERATURE', CELL_CENTERED=T /
&BNDF QUANTITY='CONVECTIVE HEAT FLUX', CELL_CENTERED=T /
&BNDF QUANTITY='HEAT TRANSFER COEFFICIENT', CELL_CENTERED=T /

&SLCF PBZ=0.5, QUANTITY='TEMPERATURE', CELL_CENTERED=T /

&DEVC ID='HF_1', QUANTITY='CONVECTIVE HEAT FLUX', SPATIAL_STATISTIC='SURFACE INTEGRAL',
XB=-0.25,0.25,-0.25,0.25,0.0,0.5, CONVERSION_FACTOR=-1, PART_ID='Cable Segment' /
&DEVC ID='HF_2', QUANTITY='ENTHALPY FLUX Z', SPATIAL_STATISTIC='AREA INTEGRAL', XB=-0.25,0.25,-0.25,0.25,0.5,0.5 /

&TAIL /