Maximum temperature at each axial location

Eric

Hi, I am handling the steady simulation problem, it is an axisymmetric problem with a sudden-expand step. There is a mass flow inlet with air on the left, another mass flow inlet with ethylene on the top and a pressure outlet on the right. For the post processing, I wanna get the maximum value of C_T(c,t) at each axial location. How can I get them in UDFs? In addition, I know there is a similar UDF in UDF Manual (2.2.8, DEFINE_ON_DEMAND), but I still have no ideas, for I don't know how to control the loops and cell threads. Is there someone who is familiar with this topic, I would appreciate so much if you can give any help and thoughts on this issue.

Thank you very much.