lagrangian- liquid range
 

Hi,
I've done the simulation of the liquid fuel injection based on aaChenBomb. Now I'm facing with post-proccesing. What I'm trying to do is extract information about range of the liquid stream over the time. Therefore, I've converted foam to VTK and also I've written python script which reads VTK files from lagrangian fields and returns interesting me points by using the GetPoint() function.
However, the results are almost constant from t=0, this confused me a lot. I'm wondering if GetPoint() returns particles coordinates, does it?
Can anyone indicate what I'm doing wrong? Maybe it is totally missaproach. Any advices or clues?

Please note that I'm very beginning in OF and also Linux:)

Kindly regards,
Rafal