UV energy absorbed
 

Hi all,
I would like to analyze a water purifier that uses UV light.
Specifically, I want to make sure that each water volume got enough energy while it flowed through the purifier.
The risk is that the fastest streamline would leave the purifier before absorbing enough energy.
I know the absorption coefficient, lamp data and functional relationship between coordinate and absorbed energy.

I basically need to integrate the energy absorbed along each streamline.

My output should be:
Streamline ID | Energy absorbed

What I want to visualize eventually is the worst streamline and the total energy absorbed.

How would you solve this?

Thanks
Adam