Default storage specification for the swale-design optimiser

Storage-layer search space per storage type: the infiltration box uses discrete stack levels (default: the brute-force grid levels), the gravel trench is continuous with bounds coupled to the box level range by coupling_factor (default 3, approximating the usable-porosity ratio 0.95 / 0.3).

Usage

default_storage_spec(
  levels = sickerbox_level_presets()$brute_force,
  coupling_factor = 3,
  gravel_tol = 25
)

Arguments

levels

Numeric vector of infiltration-box stack heights in mm.

coupling_factor

Factor between gravel-trench bounds and the box level range.

gravel_tol

Bisection tolerance for the continuous gravel-trench height in mm.

Value

Named list with entries infiltration_box (with levels and porosity) and gravel_trench (with bounds, tol and porosity).

Details

Each entry also carries the usable porosity of the storage layer (box 0.95, trench 0.3, matching default_storage_types()). The bisection optimiser uses it to derive its search order from the cost rates (cost per mm of storage capacity); without a porosity entry it falls back to the default-rate hierarchy (smallest storage level first).