dot-get_dwv: d_wv: water vapour gradient (mol / m ^ 3)

Description Usage Arguments Details Value Examples

Description

d_wv: water vapour gradient (mol / m ^ 3)

Usage

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.get_dwv(T_leaf, pars, unitless)

Arguments

T_leaf

Leaf temperature in Kelvin

pars

Concatenated parameters (leaf_par, enviro_par, and constants)

unitless

Logical. Should function use parameters with units? The function is faster when FALSE, but input must be in correct units or else results will be incorrect without any warning.

Details

Water vapour gradient: The water vapour pressure differential from inside to outside of the leaf is the saturation water vapor pressure inside the leaf (p_leaf) minus the water vapor pressure of the air (p_air):

d_wv = p_leaf / (R T_leaf) - RH p_air / (R T_air)

Note that water vapor pressure is converted from kPa to mol / m^3 using ideal gas law.

Symbol R Description Units Default
p_air p_air saturation water vapour pressure of air kPa calculated
p_leaf p_leaf saturation water vapour pressure inside the leaf kPa calculated
R R ideal gas constant J / (mol K) 8.3144598
RH RH relative humidity % 0.50
T_air T_air air temperature K 298.15
T_leaf T_leaf leaf temperature K input

Value

Value in mol / m^3 of class units

Examples

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# Water vapour gradient: 

leaf_par <- make_leafpar()
enviro_par <- make_enviropar()
constants <- make_constants()
pars <- c(leaf_par, enviro_par, constants)
T_leaf <- set_units(300, K)
T_air <- set_units(298.15, K)
p_leaf <- set_units(35.31683, kPa)
p_air <- set_units(31.65367, kPa)

d_wv <- p_leaf / (pars$R * T_leaf) - pars$RH * p_air / (pars$R * T_air)

cdmuir/tealeaves documentation built on June 21, 2020, 2:32 a.m.