uh_breakage_rou: Critical wind speed for breakage - Roughness method.
In tom-locatelli/fgr: R Version of the ForestGALES wind risk model

Calculates the critical wind speed for breakage using the roughness method.

uh_breakage_rou(
  mean_ht,
  mean_dbh,
  spacing,
  dist_edge,
  gap_size,
  mean_cr_width,
  mean_cr_depth,
  moe,
  mor,
  fknot,
  n_drag,
  c_drag,
  drag_upper_limit,
  stem_vol,
  stem_density,
  crown_density,
  snow_depth,
  snow_density,
  ro,
  fgr_constants
)

`mean_ht`	Arithmetic mean height of the trees in the stand (m).
`mean_dbh`	Mean dbh of all trees in the stand (cm). Dbh is diameter at breast height, measured at 1.3m above the ground. Essential.
`spacing`	Mean distance between trees (m).
`dist_edge`	Distance from the upwind edge (m).
`gap_size`	Length of the upwind gap (m).
`mean_cr_width`	Width of the crown of the mean tree in the stand (m).
`mean_cr_depth`	Depth of the crown of the mean tree in the stand (m).
`moe`	Modulus of Elasticity of green wood (MPa).
`mor`	Modulus of Rupture of green wood (MPa).
`fknot`	Knot factor (dimensionless).
`n_drag`	N parameter of the drag coefficient formula (dimensionless).
`c_drag`	C parameter of the drag coefficient formula (dimensionless).
`drag_upper_limit`	Maximum wind speed used during the experiments from which `n_drag` and `c_drag` were derived (m*s-1).
`stem_vol`	Stem volume of the mean tree in the stand (m^3).
`stem_density`	Density of green wood of the stem (kg m-3).
`crown_density`	Crown density of the mean tree in the stand (kg m-3).
`snow_depth`	Depth of layer of snow on tree crown (cm).
`snow_density`	Density of snow (kg m-3).
`ro`	Air density (kg m-3).

A list including: The critical wind speed (m s-1) for breakage at zero plane displacement height for the roughness method; The applied bending moment; The zero plane displacement height; The ratio of critical wind speed at canopy top over friction velocity (uh / u*); The deflection loading factor; The critical breaking moment; The combined effect of edge, gap, and gust on the applied bending moment.

tom-locatelli/fgr documentation built on Oct. 2, 2020, 2:09 a.m.