Heat Exchanger
 

Hello evry Body!
I have a problem with results in ANSYS cfx
THe results are reflex for as Solid domain.
why did they be those?
from the Picture we notice that lates fins are hotter than the earliest fins for inlet where the water is hotter !
Is this wrong?
How I fix it?http://www.m5zn.com/newuploads/2014/...5ddfa415a9.png
http://www.m5zn.com/newuploads/2014/...eb76aedfad.png
http://www.m5zn.com/newuploads/2014/...0a6403ede8.png

Are you sure your simulation is accurate? Have you done the normal checks - mesh, time step and convergence sensitivity?

Also, what is happening at the outside of the fins? Are they loosing heat to air? Soem other fluid? And how is it constrained?

Yes I checked for every things
I did a lot of simulations for alot of models of heat exchanger
and the same problem was there in every model
the boundary conditions for this model are:
for water : inlet (80[c],0.1[m\s],1[atm]) ,outlet(1[atm])
for solid(ALuminum) : convection with heat coffeicet equal 10
for this model I don't take air domain

this is another model with three domains : water , Air (enclouser) and solid
the same problem is found
the boundary conditions : the same for water (80 c , 0.1 m\s ,.........)
and for air (20 [c], inlet (1 m\s)
http://im71.gulfup.com/x5TJo9.png
http://im71.gulfup.com/7Ehugs.png

this another model with 3 domains : air ,water, solid (aluminum)
the wrong is with solid domain only.
http://im75.gulfup.com/uEPsv8.png

Please I need help.

Please post your output file, and an image showing your full domain and the boundary conditions you applied.