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Group canopy_fire

Modules > canopy_fire

Fire-related calculations for flame height and wind adjustment factors.

Public Functions

Type Name
subroutine canopy_fire_mod::canopy_flameh (FLAMEH_OPT FLAMEH_OPT, FLAMEH_SET FLAMEH_SET, DX DX, MODRES MODRES, FRP_IN FRP_IN, FRP_FAC FRP_FAC, FCH FCH, LU_OPT LU_OPT, VTYPE VTYPE, FLAMEH_CAL FLAMEH_CAL, MIDFLAMEPOINT MIDFLAMEPOINT, FLAMEH FLAMEH)
Calculate flame height and midflame point.
subroutine canopy_fire_mod::canopy_waf (HCM HCM, LAMBDARS LAMBDARS, HREF HREF, FLAMEH FLAMEH, FIRETYPE FIRETYPE, D_H D_H, ZO_H ZO_H, CANBOTMID CANBOTMID, CANTOPMID CANTOPMID, WAF WAF)
Calculate Wind Adjustment Factor for fire spread.

Public Functions Documentation

function canopy_flameh

Calculate flame height and midflame point. 

subroutine canopy_fire_mod::canopy_flameh (
    FLAMEH_OPT FLAMEH_OPT,
    FLAMEH_SET FLAMEH_SET,
    DX DX,
    MODRES MODRES,
    FRP_IN FRP_IN,
    FRP_FAC FRP_FAC,
    FCH FCH,
    LU_OPT LU_OPT,
    VTYPE VTYPE,
    FLAMEH_CAL FLAMEH_CAL,
    MIDFLAMEPOINT MIDFLAMEPOINT,
    FLAMEH FLAMEH
)

Computes flame height and midflamepoint layer needed for WAF calculation using various methods including FRP-based calculations and user-defined values

Parameters:

  • FLAMEH_OPT Integer for flame height calculation option (0=calculate, 1=user set, etc.)
  • FLAMEH_SET User set flame height value (m)
  • DX Grid cell distance using haversine formula (m)
  • MODRES Canopy model input vertical resolution (m)
  • FRP_IN Model input Fire Radiative Power (MW/grid cell area)
  • FRP_FAC FRP tuning factor for flame height calculation
  • FCH Grid cell canopy height (m)
  • LU_OPT Supported land use classifications
  • VTYPE Dominant vegetation type
  • FLAMEH_CAL Option of vegetation type dependent FRP to flame height relationships
  • MIDFLAMEPOINT Index of the mid-flame point
  • FLAMEH Calculated flame height (m)

Author:

P. C. Campbell

Date:

Oct 2022

Note:

Supports multiple flame height calculation methods and crown fire detection

function canopy_waf

Calculate Wind Adjustment Factor for fire spread. 

subroutine canopy_fire_mod::canopy_waf (
    HCM HCM,
    LAMBDARS LAMBDARS,
    HREF HREF,
    FLAMEH FLAMEH,
    FIRETYPE FIRETYPE,
    D_H D_H,
    ZO_H ZO_H,
    CANBOTMID CANBOTMID,
    CANTOPMID CANTOPMID,
    WAF WAF
)

Computes Wind Adjustment Factor for fire spread for either sub-canopy or above-canopy fires using Massman et al. (2017) formulations

Parameters:

  • HCM Height of canopy top (m)
  • LAMBDARS Value representing influence of roughness sublayer (dimensionless)
  • HREF Reference height above the canopy (m)
  • FLAMEH Flame height for above canopy fire (m)
  • FIRETYPE Fire type: 1=Above Canopy Fire, 0=Below Canopy Fire
  • CANBOTMID Mid-flame canopy bottom wind reduction factor (dimensionless)
  • CANTOPMID Mid-flame canopy top wind reduction factor (dimensionless)
  • D_H Zero-plane displacement height (d/h) (dimensionless)
  • ZO_H Surface (soil+veg) roughness length (zo/h) (dimensionless)
  • WAF Wind Adjustment Factor (dimensionless)

Author:

P. C. Campbell

Date:

Jun 2022

Note:

Based on Massman et al. (2017) algorithms for fire behavior prediction Massman, W.J., J.M. Forthofer, M.A. Finney (2017). An improved canopy wind model for predicting wind adjustment factors and wildland fire behavior. Canadian Journal of Forest Research, 47(5), 594-599. https://doi.org/10.1139/cjfr-2016-0354