UDF for Latent Heat in VOF model
 

I'm trying to validate a paper on pulsating heat pipes using VOF model and in it, saturation temperature was given as a function of pressure and latent heat was given as a function of saturation temperature.

I found a UDF for saturation temperature in this forum that I could edit, so I'm good on that front. But coming to the latent heat part, as Fluent calculates latent heat by the difference of SSEs, how am I supposed to give a function for latent heat? I'm completely new to UDFs so any help will be greatly appreciated.

These is the equation that I have to give

L = (2.5 * 10^6) - ((2.386*10^3)*(sat_temp-273))