Need some help for total liquid fraction
 

Hi there,

I have a small block (3-D) in which I want to analyze its liquid fraction. I supply a heat flux through its top surface and the block starts to melt downwards.

By displaying contours of liquid fraction, I can see the contours of liquid fraction at different times of simulation, i.e at 5mins or 10min.

For my project, I need to plot a graph of total liquid fraction versus time at 5mins interval up to a time of 60 mins. May I ask if in Fluent, is there any function that allows me to know the TOTAL liquid fraction in the small block, i.e, the volume of the the block that has already melted (So far, I've only been able to display the liquid fraction contours).

I've been able to get this advice from a friend "Anyway, you might be able to get average or overall liquid fraction by creating your own custom field function or user-defined scalar (in the define menu). Don't forget that the liquid fraction value is calculated purely from temperature so you could also use temperature data to create a custom field function which gives liquid fraction (i.e. find how much volume is over/under that phase change temp/range)."

Can anyone guide me along? How do I create my own custom field function?

Thanks in advance for your help!

Cheers! Linus