An Introduction and Demonstration

Document Sample
An Introduction and Demonstration Powered By Docstoc
					       How to Use FDS 3.0 and
          Smokeview 3.0

        An Introduction and
          Demonstration


           Zhuman Fu, Post Doctoral Fellow
  Fire Safety Engineering Group, Carleton University




Outline


   •   Set up and Run fds
   •   Create an Input File
   •   Handle Output Files
   •   Use Smokeview for Visualization
   •   A One-Room Example
Download and Install


  •   Go to the website:http://fire.nist.gov/fds
  •   Click “Downloads” link on the left side
  •   Download fdsall_300.exe file to your PC
  •   Run the file and follow the instructions
  •   All the components are included




Run and Stop fds 3.0


• Open a MS-DOS or command prompt window
• Change to the directory of the input file
• Type in “fds3<casename.data” to run a case
  (“casename.data” is the input file name)
• Create a file “casename.stop” to stop the run
Structure of an Input File


               Parameter Names
       &SLCF PBY=0.75, QUANTITY='DENSITY' /

   Group Name
                            Values




  Name a Problem

                  Group &HEAD

   • CHID:  Character string of 30 characters or
            less used to tag a problem and its
            output files. No periods or spaces are
            allowed in CHID.
   • TITLE: Character string of 60 characters or
            less that describes the problem.
Set up the
Simulation Time


                        &TIME

• Define the simulation time and initial time step size
• TWFIN: Simulation time (Time When FINished) (1s)
• DT: Initial time step size ( 5(δxδyδz )1/ 3 / gH )




Create a Physical and
Computational Domain
                 Group &PDIM
• Define the physical domain
• XBAR0, XBAR, YBAR0, YBAR, ZBAR0, ZBAR

                    Group &GRID
•   Define the computational domain
•   IBAR, JBAR, KBAR
•   Number of cells in the form 2l3m5n
•   Refer to the table on p.17 of fds3 user’s guide.
    Create a Solid
    Obstruction or Block

                      Group &OBST
•   Define a solid obstruction or block
•   XB: 6-value coordinates X1, X2, Y1, Y2, Z1, Z2
•   SURF_ID: Surface ID for one surface condition
•   SURF_IDS: IDs of the top, sides and bottom surfaces
•   SURF_ID6: IDs of the complete six surfaces
    (‘INERT’ refers to default boundary surface)




    Create a Vent


                       Group &VENT
    • Define ventilation locations and properties
    • XB: Coordinates, two of six the same
    • SURF_ID: Vent ID
      Note: Two reserved values: ‘OPEN’, ‘MIRROR’.
How To Use SURF Group

                     Group &SURF
 • Function
    – Define thermal boundary conditions
    – Define flow boundary condition
    – Define a fire source
 • General Parameters
    – ID: Surface ID, linking to the obstruction




    Thermal Boundary
    Condition
                   Group &SURF
 • Fixed temperature
      TMPWAL
 • Fixed heat flux
      HEAT_FLUX, positive for heating up gas
 • Thermally thin sheet
      C_DELTA_RHO: product of 3 properties
 • Thermally thick solid
      ALPHA: thermal diffusivity
      KS: thermal conductivity
      DELTA: thickness of material
 (EMISSIVITY: Solid surface radiant emissivity)
Flow Boundary Condition

               Group &SURF

      • VEL: Normal direction velocity
      • VOLUME_FLUX: Volume flux
      • VEL_T: Tangential direction velocity
      • TMPWAL: Temperature for inlet gas




 Define a Fire
                Group &SURF
 • Specify an HRR or burning rate
   – HRRPUA: HRR per unit area in kW/m2
 • Calculating HRR Based on Heat Feedback
   – HEAT_OF_VAPORIZATION: In kJ/kg
   – TMPIGN: Ignition temperature in °C
 • A Burnout Fire
   – DENSITY: In kg/m3, if fuel disappears
   – SURFACE_DENSITY: In kg/m2, if fuel is intact
Define a Reaction
                            Group &REAC
• ID
     – Identity of the specified fuel
• NU_FUEL, NU_O2, NU_CO2, NU_H2O
     – Stoichiometric coefficients of fuel, O2, CO2, H2O
• SOOT_YIELD, CO_YIELD
     – Soot and CO yields
• MW_FUEL
     – Molecular weight of fuel
• EPUMO2
     – Energy per unit mass O2 (13, 100 kJ/kg)
• RADIATIVE_FRACTION
     – Fraction of HRR through radiation (0.35)




Specify a sprinkler
                            Group &SPRK

•   XYZ: Coordinates of X, Y, Z; a triplet value
•   MAKE: A sprinkler name in the sprinkler file
•   T_ACTIVATE: Activation time
•   T_DEACTIVATE: Deactivation time
•   ORIENTATION: Spray direction
       Note: The characteristic information of a
             given sprinkler is contained in a
             separate file “sprinkler_name.spk”.
Specify a Heat Detector


                 Group &HEAT

• XYZ: Coordinates of x y z, a triplet value
• RTI: Response Time Index
• ACTIVATION_TEMPERATURE: Activation temperature




Setup Tracing Particles

                 Group &PART
 • Function
    –View tracer particles injected into the flow
     field from vents or obstacles
 • Parameter
    –DTSAM: Sampling interval in s; default
                  value TWFIN/NFRAMES
Miscellaneous Parameters
                           Group &MISC

  •   NFRAMES: Number of frames to output data (1000)
  •   REACTION: Fuel name (PROPANE)
  •   DATABASE: Database file name (database3.data)
  •   DATABASE_DIRECTORY: Directory of database file
  •   TMPA: Ambient temperature (20 °C)
  •   TMPO: Outside temperature (20 °C)
  •   U0, V0, W0: Initial velocity in X, Y, Z directions (0)
  •   SURF_DEFAULT: Default surface (‘INERT’)




 Output Quantities

  •   Output a variable at a point with time
  •   Output a variable with time on a plane
  •   Output quantities with time on the boundary surface
  •   Output an isosurface of a quantity with time
  •   Output flow field over the entire grid
  •   Default MS Excel Output Files
  •   Convert fds Output Files
Output at a Point

                    Group &THCP

•   File Name: casename_tc.csv
•   XYZ: Coordinates, a triplet value
•   QUANTITY: Refer to Tables 2, 3,4 in the guide
•   LABEL: Identification label
•   IOR: Orientation index; ±1, ±2, ±3 = ±X, ±Y, ±Z
•   DTSAM: Sampling interval in s ( TWFIN/NFRAMES)




Output on a Plane
                     Group &SLCF

• File Name: casename_n.sf
• XB: 6-value coordinates; with its 2 or 4 values the
       same, indicating a plane or line
• QUANTITY: Refer to Table 2 in the guide
• DTSAM: Sampling interval in s (TWFIN/NFRAMES)
• PBX: A plane perpendicular to X coordinate
• PBY: A plane perpendicular to Y coordinate
• PBZ: A plane perpendicular to Z coordinate
Output the Boundary File


                     Group &BNDF

 • File Name: casename_n.bf
 • QUANTITY: Refer to Table 3 in the guide
 • DTSAM: Sampling interval in s ( TWFIN/NFRAMES/2)




 Output an Isosurface


                      Group &ISOF

 •   File Name: casename_n.iso
 •   QUANTITY: Gas phase quantity (mixture fraction)
 •   VALUES(n): Values of a quantity
 •   DTSAM: Sampling interval in s (TWFIN/NFRAMES)
Output Flow Field

                    Group &PL3D

• File Name: With .q extension
• DTSAM: Sampling interval in s (TWFIN/5)
• QUANTITIES: Quantities of plot 3d output; default
       values are ‘TEMPERATURE’, ‘U-VELOCITY’, ‘V-
       VELOCITY’, ‘W-VELOCITY’, ‘HRRPUV’; the first and
       fifth quantities can be changed with parameters
       QUANTITIES(1) and QUANTITIES(5).




Excel Output Files


• &THCP Files
   – Any THCP output (casename_tc.csv)
• Default output files
   – HRR (casename_hrr.csv)
   – Total mass of species (casename_mass.csv)
   – Relationship of mixture fraction with mass fraction
     of each species (casename_state.csv)
Convert fds Output Files



 • Run fds2ascii at the command prompt
 • Answer questions prompted by the program
 • Get the converted file “casename.dat”.




Some Other
Special Features

 •   Restart a calculation
 •   Stretch the Grid
 •   Initial Conditions
 •   Create or Remove Obstructions
 •   Open or Close Vents
 •   Extra Species
 •   Finite-Rate or Premixed Combustion
 •   Non-rectangular Geometry
 Run Smokeview to
 Visualize fds Results


Run fds to create a file “casename.smv”
Double click this file to start Smokeview interface
Right-click the interface to show the main menu
Select the Load/Unload command to choose a file
Use the Help command to show keyboard shortcuts




 Schematic of the Test
 Room with Door Ventilation

                 Heat Release Rate at: 330, 980 kW




         2.5 m
                   Propane Burner                    2.0 m

                                         0.6 m

                              3.6 m
Coordinate System




         Z



                 Y


        Origin                 X




  Input Data
                           Fuel Properties
    Fuel                               Propane [C3H8]
    Nominal HRR [kW]                      330, 980
                 Thermal Properties of Boundaries
                               Ceiling      Wall      Floor
    Thickness [m]              0.066       0.054      0.044
    Density [kg/m3]             449         449        770
    Conductivity [W/(m K)]      0.10        0.10      0.14
    Specific heat [J/(kg K)]    1090        1090       900
    Diffusivity [m2/s]         2.0E-7      2.0E-7    2.0E-7
                             Dimensions
                              Depth [m] Width [m] Height [m]
    Compartment                  2.5         3.6       2.5
    Vent                        N/A          0.7       2.0
    Burner’s surface             0.7         1.2       0.6
Part 1 of the Input File
    • &HEAD CHID='StdRoom330', TITLE=‘330 kW Fire Test’ /
    • &PDIM XBAR=3.6, YBAR=2.5, ZBAR=2.5/
    • &GRID IBAR=36, JBAR=25, KBAR=25/
    • &TIME TWFIN=1200. /
    • &MISC SURF_DEFAULT='WALL' /
    • &OBST XB=1.7, 1.9, 1.2, 1.3, 0.0, 0.5, SURF_ID='INERT' /
    • &OBST XB=1.2, 2.4, 0.9, 1.6, 0.5, 0.6,
            SURF_IDS='Fire', 'WALL', 'WALL' /
    • &OBST XB=0.0, 3.6, 0.0, 2.5, 2.5, 2.5, SURF_ID='Ceiling' /
    • &OBST XB=0.0, 3.6, 0.0, 2.5, 0.0, 0.0, SURF_ID='Floor' /
    • &VENT XB=3.6, 3.6, 0.9, 1.6, 0.0, 2.0, SURF_ID="OPEN" /




Part 2 of the Input File
•       &SURF ID='WALL'
•         FYI='Thermally-thick material'
•         ALPHA=2.0E-7
•         KS=0.1
•         DELTA=0.054 /
•       &SURF ID='Ceiling'
•         FYI='Thermally-thick material'
•         ALPHA=2.0E-7
•         KS=0.1
•         DELTA=0.066 /
•       &SURF ID='Floor'
•         FYI='Thermally-thick material'
•         ALPHA=2.0E-7
•         KS=0.14
•         DELTA=0.044 /
•       &SURF ID='Fire', HRRPUA=393., RGB=1.0, 0.0, 0.0 /
Part 3 of the Input File
• &THCP XYZ=1.0, 0.6, 1.7, QUANTITY='TEMPERATURE',
  LABEL='TU', DTSAM=10. /
• &THCP XYZ=1.0, 0.6, 0.5, QUANTITY='TEMPERATURE',
  LABEL='TL', DTSAM=10. /
• &THCP XYZ=0.0, 0.6, 1.7, QUANTITY='TEMPERATURE',
  LABEL='TWU', DTSAM=10. /
• &THCP XYZ=0.0, 0.6, 0.5, QUANTITY='TEMPERATURE',
  LABEL='TWL', DTSAM=10. /
• &THCP XYZ=1.0, 0.6, 0.0, QUANTITY='TEMPERATURE',
  LABEL='TFL', DTSAM=10. /
• &THCP XYZ=1.0, 0.6, 0.0, QUANTITY='RADIATIVE_FLUX',
  IOR=3, LABEL='RADI', DTSAM=10. /
• &THCP XYZ=1.0, 0.6, 0.0,
  QUANTITY='GAUGE_HEAT_FLUX',IOR=3, LABEL='GAUGE',
  DTSAM=10. /




Part 4 of the Input File
• &BNDF QUANTITY='WALL_TEMPERATURE' /

•   &SLCF PBY=1.2, QUANTITY='TEMPERATURE' /
•   &SLCF PBY=1.2, QUANTITY='HRRPUV' /
•   &SLCF PBY=1.2, QUANTITY='MIXTURE_FRACTION' /
•   &SLCF PBY=1.2, QUANTITY='RADIANT_INTENSITY' /
•   &SLCF PBY=1.2, QUANTITY='ABSORPTION_COEFFICIENT' /
•   &SLCF PBY=1.2, QUANTITY='PRESSURE' /
•   &SLCF PBY=1.2, QUANTITY='H' /
•   &SLCF PBY=1.2, QUANTITY='U-VELOCITY' /
•   &SLCF PBY=1.2, QUANTITY='carbon dioxide' /
•   &SLCF PBY=1.2, QUANTITY='oxygen' /

• &PL3D DTSAM=10. /
Comparison of Results


   Parameters   TU     TL     TWU    TWL    TFLR   m AV
                                                    &         q IF
                                                                   2
     Units      (°C)   (°C)   (°C)   (°C)   (°C)   (kg/s)   (kW/m )
                HRR=330 (kW), Duration Time=30 (min)
   EXPTL.       370    84     315    187    180    0.87       3.8
   CFAST        457    48     426    372    334    0.64       16
   FDS          326    51     339    84     71     0.69       5.0
                HRR=980 (kW), Duration Time=20 (min)
   EXPTL.       796    236    728    471    551    1.01        33
   CFAST        901    118    885    852    841    0.89       107
   FDS (LES)    775    160    804    330    257    0.88        53
   FDS (DNS)    607    463    581    533    540    0.63        27




Demonstration



  • Demonstrating Results

				
DOCUMENT INFO