Natural convection of water

lbmagis · October 26, 2014, 14:05

Hello,
I dident get the good results when modeling natural convection into 2D cavity filled with water, using ansys Fluent 6.3, Boussinesq approximation, Laminar flow, steady case

Any suggestions to overcome this drawbacks???
Thank you in advance

dreamz · October 27, 2014, 01:06

Did you specify gravity?

lbmagis · October 27, 2014, 11:18

Quote:

Originally Posted by dreamz

Did you specify gravity?

Hello dreamz,
Thak you for replying!
yes i did.
the problem that the isotherms are parallel (it looks like conduction isotherms), when i compared with results found in literature, it was pretty much different!!!
All the best

dreamz · October 27, 2014, 11:40

Is it possible for you to share your dimensions.. Or else I will try with my own dimensions and will get back to you..

lbmagis · October 27, 2014, 14:38

Could you please paste your isotherms here ??? and the thermophysical properties for water ???

dreamz · October 27, 2014, 21:43

I am working on it.. I have kept the side walls at hot and cold temperatures each and the top and bottom walls at room temperature.. Are these okay for you or you are using some different boundary conditions?

lbmagis · October 28, 2014, 01:18

Horizontal walls kept adiabatic, the others are differentially heated,,, but i wanna know the thermophysical properties you're working with!
Thanx

dreamz · October 29, 2014, 07:40

I have got convergence for your problem. I use water (l) which is in the fluent database under materials. Under density I select boussinesq approximation with density value corresponding to my ref. Temperature. Thermal expansion, I have specified as corresponding to ref temp. Tell me for what values of grashof number are you looking for results?

October 26, 2014, 14:05	Natural convection of water	#1
lbmagis Member amine Join Date: Jun 2012 Posts: 65 Rep Power: 13	Hello, I dident get the good results when modeling natural convection into 2D cavity filled with water, using ansys Fluent 6.3, Boussinesq approximation, Laminar flow, steady case Any suggestions to overcome this drawbacks??? Thank you in advance

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Natural convection in water	CneSpaulding	STAR-CCM+	8	July 9, 2015 04:18
natural convection with stagnation inlet and water?	KyleA&M	STAR-CCM+	2	May 21, 2013 11:48
Multiregion Heat Transfer + natural convection (water) with chtMultiRegionFoam	fattychickenrun	OpenFOAM	5	October 31, 2011 16:53
natural convection problem with radiation	jorien	CFX	0	October 14, 2011 09:26
How model natural convection in water?	Fiska	FLUENT	4	January 28, 2010 03:23

October 27, 2014, 01:06		#2
dreamz Member Ashutosh Join Date: Jul 2013 Posts: 98 Rep Power: 12	Did you specify gravity?

October 27, 2014, 11:40		#4
dreamz Member Ashutosh Join Date: Jul 2013 Posts: 98 Rep Power: 12	Is it possible for you to share your dimensions.. Or else I will try with my own dimensions and will get back to you..

October 27, 2014, 14:38		#5
lbmagis Member amine Join Date: Jun 2012 Posts: 65 Rep Power: 13	Could you please paste your isotherms here ??? and the thermophysical properties for water ???

October 27, 2014, 21:43		#6
dreamz Member Ashutosh Join Date: Jul 2013 Posts: 98 Rep Power: 12	I am working on it.. I have kept the side walls at hot and cold temperatures each and the top and bottom walls at room temperature.. Are these okay for you or you are using some different boundary conditions?

October 28, 2014, 01:18		#7
lbmagis Member amine Join Date: Jun 2012 Posts: 65 Rep Power: 13	Horizontal walls kept adiabatic, the others are differentially heated,,, but i wanna know the thermophysical properties you're working with! Thanx

October 29, 2014, 07:40		#8
dreamz Member Ashutosh Join Date: Jul 2013 Posts: 98 Rep Power: 12	I have got convergence for your problem. I use water (l) which is in the fluent database under materials. Under density I select boussinesq approximation with density value corresponding to my ref. Temperature. Thermal expansion, I have specified as corresponding to ref temp. Tell me for what values of grashof number are you looking for results?