R/total_fuel_consumption.r

In jordan-evens-nrcan/cffdrs: Canadian Forest Fire Danger Rating System

#' Total Fuel Consumption calculation
#'
#' @description Computes the Total (Surface + Crown) Fuel Consumption by Fuel
#' Type.
#' All variables names are laid out in the same manner as FCFDG (1992) or
#' Wotton et. al (2009)
#'
#' Forestry Canada Fire Danger Group (FCFDG) (1992). "Development and
#' Structure of the Canadian Forest Fire Behavior Prediction System."
#' Technical Report ST-X-3, Forestry Canada, Ottawa, Ontario.
#'
#' Wotton, B.M., Alexander, M.E., Taylor, S.W. 2009. Updates and revisions to
#' the 1992 Canadian forest fire behavior prediction system. Nat. Resour.
#' Can., Can. For. Serv., Great Lakes For. Cent., Sault Ste. Marie, Ontario,
#' Canada. Information Report GLC-X-10, 45p.
#'
#' @param FUELTYPE The Fire Behaviour Prediction FuelType
#' @param CFL      Crown Fuel Load (kg/m^2)
#' @param CFB      Crown Fraction Burned (0-1)
#' @param SFC      Surface Fuel Consumption (kg/m^2)
#' @param  PC      Percent Conifer (%)
#' @param PDF      Percent Dead Balsam Fir (%)
#' @param option   Type of output (TFC, CFC, default="TFC")
#'
#' @returns TFC Total (Surface + Crown) Fuel Consumption (kg/m^2) OR
#' CFC Crown Fuel Consumption (kg/m^2)
#'
#' @noRd


crown_fuel_consumption <- function(FUELTYPE, CFL, CFB, PC, PDF) {
  # Eq. 66a (Wotton 2009) - Crown Fuel Consumption (CFC)
  CFC <- CFL * CFB
  CFC <- ifelse(
    FUELTYPE %in% c("M1", "M2"),
    # Eq. 66b (Wotton 2009) - CFC for M1/M2 types
    PC / 100 * CFC,
    ifelse(
      FUELTYPE %in% c("M3", "M4"),
      # Eq. 66c (Wotton 2009) - CFC for M3/M4 types
      PDF / 100 * CFC,
    CFC)
  )
  return(CFC)
}

total_fuel_consumption <- function(
    FUELTYPE, CFL, CFB, SFC, PC, PDF,
    option = "TFC") {
  CFC <- crown_fuel_consumption(FUELTYPE, CFL, CFB, PC, PDF)
  # Return CFC if requested
  if (option == "CFC") {
    return(CFC)
  }
  # Eq. 67 (FCFDG 1992) - Total Fuel Consumption
  TFC <- SFC + CFC
  return(TFC)
}

.TFCcalc <- function(...) {
  .Deprecated("total_fuel_consumption")
  return(total_fuel_consumption(...))
}