[Eole]

Hi all!

I'm a student trying to modelise a heat exchanger on fluent. I use to work on Star-CCM+ so I don't really know fluent.

The simulation involve air (exhaust gas) and water vapor in a simple coaxial tube in conter-flow (3D simulation).

Exhaust gas:
Pressure: 1.5bar
Velocity: 61 m/s (mass flow 0.132 kg/s)
density: 0.4962 kg/m^3
Temperature inlet: 1047 K

Water Vapour:
Pressure: 4bar
Velocity: 28 m/s (mass flow 0.03 m/s)
density: 0.5542 kg/m^3
Temperature inlet: 416 K

Boundary conditions
Both velocity inlet customised with the number mentionned above
Both pressure outlet customised with number mentionned above
No slip conditions on walls
Thickness of walls where heat transfer happens: 5mm (in total)
Wall without heat transfer considered as adiabatic


My problem is ... both fluid temperature are decreasing and pressure in the exhaust pipe is not constant.

I'm not really a specialist in heat transfer and so in CFD simulation for heat transfer so maybe there is not enough detail here to let you help me. Let me know

Thank you!

[evswbok]

i am facing the same problem