Fuel_model

The Anderson (1982) 13-category surface fuel table exactly as fire_behavior carries it (physics/fuel_anderson_mod.F90 Init_anderson_fuel_model, plus the derived quantities of share/fuel_mod.F90 Calc_wind_adjustment_factor, state/state_mod.F90 Init_fuel_vars and fmc_wrffire_mod Init_fmc_wrffire), as a lookup on the integer category code: fuel load fgi (fire_behavior's own kg/m^2 values), bed depth, mass-loss weight, chaparral flag, particle density, surface-area-to-volume ratio, mineral contents, moisture of extinction, the Albini (1976) 1-h/10-h/100-h/1000-h/live load proportions, the canopy fuel parameters, and the derived wind adjustment factor, fuel e-folding time and fuel-moisture class weights. Category 14 is 'no fuel'. Each property is a piecewise-linear interpolation through the 14 integer nodes, exact at the nodes (the same spelling as the EarthSciModels wildland_fire/fuel_model_lookup.esm, which this component does NOT reuse because its numbers differ: that file converts Anderson's ton/acre loads to SI -- 0.449 kg/m^2 for category 2 where fire_behavior has 0.896 -- rounds the depths differently (1.8288 vs 1.829 m) and divides the residence time by 0.8514 instead of 0.85). Tests are the dumped fuel tables and waf array of the instrumented fire_behavior (real32), rel 1e-6 on the transcribed literals and 1e-5 on the derived waf.

Anderson (1982) 13-fuel-model fuel-bed depth lookup: maps integer fuel model code (1–13) to fuel bed depth δ in metres, converted from the upstream ft values in ANDERSON_FUEL_DATA via δ_m = depth_ft × 0.3048. Out-of-range codes (including LANDFIRE non-burnable codes 91–99) return the fuel-model-1 default 1.0 × 0.3048 = 0.3048 m. Migrated from WildlandFire.jl src/coupling.jl:125 (`@register_symbolic fuel_depth`). Resolves the gt-p3ep blocking gap via ifelse + interp.linear over the integer axis [1..13].

Anderson (1982) 13-fuel-model heat content lookup: maps integer fuel model code (1–13) to low heat content in J/kg (8,000 BTU/lb for all Anderson models = 18,608,000 J/kg). Non-burnable LANDFIRE codes (91-99) and out-of-range codes return 0.0 J/kg. Migrated from WildlandFire.jl src/coupling.jl:127 (`@register_symbolic fuel_heat`). NOTE: fuel_heat is implementable without a lookup table because all 13 Anderson models share the same h=8000 BTU/lb; see reference notes on the gt-p3ep blocking gap for the other fuel_* functions.

Anderson (1982) 13-fuel-model total fine fuel load lookup: maps integer fuel model code (1–13) to oven-dry fuel load w₀ in kg/m², converted from the upstream lb/ft² values in ANDERSON_FUEL_DATA via w₀_kg_m2 = load_lb_ft2 × (0.45359237/0.09290304). Out-of-range codes (including LANDFIRE non-burnable codes 91–99) return the fuel-model-1 default 0.034 × (0.45359237/0.09290304) ≈ 0.1660 kg/m². Migrated from WildlandFire.jl src/coupling.jl:124 (`@register_symbolic fuel_load`). Resolves the gt-p3ep blocking gap via ifelse + interp.linear over the integer axis [1..13].

Anderson (1982) 13 fuel-model parameter lookup: maps integer fuel model code (1–13) to the six Rothermel fire spread fuel properties (σ, w₀, δ, Mₓ, h, Tᶠ). Aggregates the six registered fuel_* functions (fuel_savr, fuel_load, fuel_depth, fuel_mce, fuel_heat, fuel_weight) into a single observed-variable component. Out-of-range codes (including LANDFIRE non-burnable codes 91–99) return fuel-model-1 defaults for σ, w₀, δ, Mₓ, and Tᶠ, and 0 J/kg for h. Migrated from WildlandFire.jl@126976f2 src/coupling.jl:155 (`FuelModelLookup` @mtkmodel). Resolves the gt-p3ep blocking gap via ifelse + interp.linear for the five variable-valued properties and a simple ifelse for the constant heat content.

Anderson (1982) 13-fuel-model surface-area-to-volume ratio (SAVR) lookup: maps integer fuel model code (1–13) to σ in m⁻¹, converted from the upstream 1/ft values in ANDERSON_FUEL_DATA via σ = savr_ft / 0.3048. Out-of-range codes return the default 3500/0.3048 ≈ 11482.94 m⁻¹ (fuel model 1). Migrated from WildlandFire.jl src/coupling.jl:123 (`@register_symbolic fuel_savr`). Resolves the gt-p3ep blocking gap via ifelse + interp.linear over the integer axis [1..13].

LANDFIRE regridding model — the coupler half of the landfire loader+regridding-model split (RFC pure-io-data-loaders §6/§7; bead esm-3nc.4). Exposes the LANDFIRE fire-behavior fuel-model code (Anderson 13 / Scott & Burgan 40) on the simulation's target grid for wildland-fire coupling in EarthSciML systems.