Heat Exchanger

mmmmostafa · August 24, 2014, 18:08

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?

ghorrocks · August 24, 2014, 18:38

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?

mmmmostafa · August 25, 2014, 10:45

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

mmmmostafa · August 25, 2014, 11:04

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)

mmmmostafa · August 25, 2014, 11:12

this another model with 3 domains : air ,water, solid (aluminum)
the wrong is with solid domain only.

mmmmostafa · August 29, 2014, 16:07

Please I need help.

ghorrocks · August 29, 2014, 19:58

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

August 24, 2014, 18:08	Heat Exchanger	#1
mmmmostafa New Member Mustafa Al Hakeem Join Date: Aug 2014 Location: Hungary Posts: 5 Rep Power: 11	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?

August 24, 2014, 18:38		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,705 Rep Power: 143	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? mmmmostafa likes this.

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August 25, 2014, 10:45		#3
mmmmostafa New Member Mustafa Al Hakeem Join Date: Aug 2014 Location: Hungary Posts: 5 Rep Power: 11	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

August 25, 2014, 11:04		#4
mmmmostafa New Member Mustafa Al Hakeem Join Date: Aug 2014 Location: Hungary Posts: 5 Rep Power: 11	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)

August 25, 2014, 11:12		#5
mmmmostafa New Member Mustafa Al Hakeem Join Date: Aug 2014 Location: Hungary Posts: 5 Rep Power: 11	this another model with 3 domains : air ,water, solid (aluminum) the wrong is with solid domain only.

August 29, 2014, 16:07		#6
mmmmostafa New Member Mustafa Al Hakeem Join Date: Aug 2014 Location: Hungary Posts: 5 Rep Power: 11	Please I need help.

August 29, 2014, 19:58		#7
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,705 Rep Power: 143	Please post your output file, and an image showing your full domain and the boundary conditions you applied.