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Average single transit collision risk with no avoidance

Source: R/get_avg_prob_collision.R
get_avg_prob_collision.Rd

Calculate the average probability of collision for a single bird transit at any point across the rotor, assuming no avoidance action. Required for the Basic model calculations, where flights at collision risk height are assumed to be uniformly distributed.

Usage

get_avg_prob_collision(
  flight_speed,
  body_lt,
  wing_span,
  prop_upwind = 0.5,
  flap_glide,
  rotor_speed,
  rotor_radius,
  blade_width,
  blade_pitch,
  n_blades,
  chord_prof = chord_prof_5MW
)

Arguments

flight_speed

Numeric value. The bird flying speed (\(v\)), in metres/sec.

body_lt

Numeric value. The length of the bird (\(L\)), in metres.

wing_span

Numeric value. The wingspan of the bird (\(W\)), in metres.

prop_upwind

Numeric value between 0-1 giving the proportion of flights upwind - defaults to 0.5.

flap_glide

Numeric value representing the correction for flapping or gliding birds (\(F\)).

rotor_speed

Numeric value. The operational rotation speed, in revolutions/min.

rotor_radius

Numeric value. The radius of the rotor (\(R\)), in metres.

blade_width

Numeric value, giving the maximum blade width, in metres.

blade_pitch

Numeric value. The average blade pitch angle, the angle between the blade surface and the rotor plane (\(\gamma\)), in radians.

n_blades

An integer, the number of blades in rotor (\(b\)).

chord_prof

A data frame with the chord taper profile of the rotor blade. Function expects two named columns:

  • pp_radius, equidistant intervals of radius at bird passage point, as a proportion of rotor_radius, within the range \([0, 1]\).

  • chord, the chord width at pp_radius, as a proportion of blade_width.

Defaults to a generic profile for a typical modern 5MW turbine. See chord_prof_5MW() for details.

Value

A numeric value. The average collision probability (risk) for a bird flying through any point of the rotor circle area.

Details

Methodology and assumptions underpinning get_avg_prob_collision are described in "Stage C" of Band (2012).

Examples

       get_avg_prob_collision(
           flight_speed = 13.1,
           body_lt = 0.85,
           wing_span = 1.01,
           prop_upwind = 0.5,
           flap_glide = 1,
           rotor_speed = 15,
           rotor_radius = 120,
           blade_width = 5,
           blade_pitch = 15,
           n_blades = 3,
           chord_prof = chord_prof_5MW
           )
#> [1] 0.1494609