Fprad: Calculates view factor of organism for beam radiation

In ilyamaclean/microctools: Various worker functions for microclimc package

Calculates view factor of organism for beam radiation

Description

the view factor is the average flux density of beam radiation over the entire surface of the object relative to the flux density on a flat absobing surface facing the source

Usage

Fprad(theta, l, d, shape = "spheroid")

Arguments

theta	angle between the longitudinal axis of the animal and solar beam (degrees) as returned by thetangle()
l	length of organism (m) along longitudinal axis
d	diameter of organism (m)
shape	one of spheroid (prolate spheroid), cylinder1 (cylinder with flat ends) or cylinder2 (cylinder with hemisphere ends) or plate (flat plate - e.g. leaf)

Details

The view factor is used in calculation of absorbed radiation. It is effectively the ratio of of the projected area in the direction of the solar beam to the total surface area of the object. For a flat plate normal to the beam, the view factor is 0.5, as only have the plate faces the beam.

Value

The view factor (ranges between zero and 1, typically ~0.25)

See Also

thetangle(), Radabs()

Examples

# caterpillar on slope (orientation unknown, so calculated by averaging across all orientations)
aspect <- c(0:359)
theta<-thetangle(alt = 50, azi = 180, slope = 20, aspect)
Fp <- Fprad(theta, 0.05, 0.01, shape = "cylinder2")
plot(Fp~aspect,type="l")
Fpm <- mean(Fp) # mean viewing angle
Fpm

ilyamaclean/microctools documentation built on Jan. 25, 2023, 5:29 a.m.