[torkness]

Hello,
I want to simulate heat exchanger. Model pipe in pipe. I want to air flowing with 40°C in inside pipe and air 900°C i outside pipe. What i get is... weird.
I don't know where the problem could be.
Those are setting i made:
-Model: Energy On, Viscous Laminar
-Cell Zone Conditions: Materials inside pipes air, materials of pipes solid aluminium
-Boundary Conditions: inlets of hot/cold pipes are set up on massflow inlet, 0.01kg/s and 900°C/40°C temperature
oulets are set up to outflow
I am learning fluent for 2 months and maybe i am doing something stupid (and simple i hope so).
Yours faithfully,
Dawid Pogorzelski