dot-get_hvap: h_vap: heat of vaporization (J / mol)

In cdmuir/tealeaves: Solve for Leaf Temperature Using Energy Balance

h_vap: heat of vaporization (J / mol)

Description

h_vap: heat of vaporization (J / mol)

Usage

.get_hvap(T_leaf, unitless)

Arguments

T_leaf	Leaf temperature in Kelvin
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

Heat of vaporization: The heat of vaporization (h_\mathrm{vap}) is a function of temperature. I used data from on temperature and h_\mathrm{vap} from Nobel (2009, Appendix 1) to estimate a linear regression. See Examples.

Value

Value in J/mol of class units

References

Nobel PS. 2009. Physicochemical and Environmental Plant Physiology. 4th Edition. Academic Press.

Examples

# Heat of vaporization and temperature
## data from Nobel (2009)

T_K <- 273.15 + c(0, 10, 20, 25, 30, 40, 50, 60)
h_vap <- 1e3 * c(45.06, 44.63, 44.21, 44.00, 
                 43.78, 43.35, 42.91, 42.47) # (in J / mol)
                 
fit <- lm(h_vap ~ T_K)

## coefficients are 56847.68250 J / mol and 43.12514 J / (mol K)

coef(fit) 

T_leaf <- 298.15
h_vap <- set_units(56847.68250, J / mol) - 
           set_units(43.12514, J / mol / K) * set_units(T_leaf, K)

## h_vap at 298.15 K is 43989.92 [J/mol]

set_units(h_vap, J / mol)

tealeaves:::.get_hvap(set_units(298.15, K), FALSE)

cdmuir/tealeaves documentation built on Feb. 28, 2024, 8:21 a.m.