# dot-get_hvap: h_vap: heat of vaporization (J / mol) In cdmuir/tealeaves: Solve for Leaf Temperature Using Energy Balance

 .get_hvap R Documentation

## 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_vap) is a function of temperature. I used data from on temperature and h_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 July 24, 2022, 5:40 a.m.