heat exchanger

Nicolás

Hi, I must model how is the distribution of the temperatur in a helicoidal pipe, this pipe hat hot milk und is in a cube with cool water. I dont know how is the better way to make it.

I have problem whit the figur, i dont know if must I shape together the pipe with the cube or only the pipe? and in Fluent, which option i muss take; heat exchager?

thanks!