CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM

which Solver for Hot Cold Water mix

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   September 12, 2012, 12:55
Default which Solver for Hot Cold Water mix
  #1
New Member
 
Erkan
Join Date: May 2010
Posts: 9
Rep Power: 7
uwsa is on a distinguished road
Hi all Foam Users,

I would like to simulate a pipe flow with
two inflows ( first inflow cold 35 Celsius) (second inflow 100 Celsius)
and one outflow with the mixture of both.

The pressure is about 8 MPa.

I checked the tutorials but could not find a corresponding case.
Does anybody know which solver could be useful for my case?

Thanks a lot.
uwsa is offline   Reply With Quote

Old   September 18, 2012, 03:40
Default
  #2
Member
 
Sachin Kanetkar
Join Date: Mar 2009
Posts: 57
Rep Power: 8
sachin is on a distinguished road
Hi ...
you already have icoFoam case for flow mixing from two inlets ...
same as fluent tutorial case ...
you just need to add the temperature equation to icoFoam (wiki page already there explaining it) and run the case ...
sachin is offline   Reply With Quote

Old   July 30, 2013, 07:39
Default
  #3
Member
 
Vishal
Join Date: Jul 2013
Posts: 73
Rep Power: 4
inf.vish is on a distinguished road
Can you share your insights on the above problem?
I would like to solve a similar problem. T joint mixing of two streams of water at different temperatures.
inf.vish is offline   Reply With Quote

Old   July 30, 2013, 15:58
Default
  #4
Senior Member
 
Nima Sam
Join Date: Sep 2009
Location: Tehran, Iran
Posts: 1,123
Blog Entries: 1
Rep Power: 14
nimasam is on a distinguished road
Send a message via Yahoo to nimasam
use bouyantBoussinqSimpleFoam
__________________
Training Course on OpenFOAM at (http://www.isme.ir/)
My Weblog (http://openfoam.blogfa.com/)
nimasam is offline   Reply With Quote

Old   July 30, 2013, 22:36
Default
  #5
Member
 
Vishal
Join Date: Jul 2013
Posts: 73
Rep Power: 4
inf.vish is on a distinguished road
The problem with buoyantBoussinesqSimpleFoam is that i can set temperature boundary conditions at the two inlets but the fluid as such does not flow at the said temperature. The fluid simply carries the heat with it. I ran the case with buoyantBoussinesqSimpleFoam and looked at the temperature profiles at different times and i can see how to fluid carries the heat. That is not my aim.I want fluid at 600K to enter the inlet.
Kindly tell me the boundary conditions for having a fluid at 600K enter the inlet if you are using buoyantBoussinesqSimpleFoam.
I found a thesis paper which says about mixing of hot and cold water with turbulence and he has used dnsFoam to solve. Also, he hasn't mentioned the codes. Can you guide me further on this simple problem. I have been stuck on this problem for three days
inf.vish is offline   Reply With Quote

Old   July 31, 2013, 03:19
Default
  #6
Member
 
Vishal
Join Date: Jul 2013
Posts: 73
Rep Power: 4
inf.vish is on a distinguished road
i have attached an image showing what exactly i want to do.
Attached Images
File Type: jpg Screenshot from 2013-07-31 12:46:26.jpg (23.8 KB, 20 views)
inf.vish is offline   Reply With Quote

Old   July 31, 2013, 04:32
Default
  #7
Senior Member
 
Nima Sam
Join Date: Sep 2009
Location: Tehran, Iran
Posts: 1,123
Blog Entries: 1
Rep Power: 14
nimasam is on a distinguished road
Send a message via Yahoo to nimasam
what contour is it? is it temperature contour?
__________________
Training Course on OpenFOAM at (http://www.isme.ir/)
My Weblog (http://openfoam.blogfa.com/)
nimasam is offline   Reply With Quote

Old   July 31, 2013, 04:35
Default
  #8
Member
 
Vishal
Join Date: Jul 2013
Posts: 73
Rep Power: 4
inf.vish is on a distinguished road
Yes that is the temperature contour.
inf.vish is offline   Reply With Quote

Old   July 31, 2013, 04:36
Default
  #9
Member
 
Vishal
Join Date: Jul 2013
Posts: 73
Rep Power: 4
inf.vish is on a distinguished road
This example is very simple to solve on fluent. Why the difficulty in solving in OpenFOAM?
I understand that buoyantBoussinesqSimpleFoam can be used. But how do i achieve the fluid entering at different temperatures.
inf.vish is offline   Reply With Quote

Old   July 31, 2013, 04:43
Default
  #10
Senior Member
 
Nima Sam
Join Date: Sep 2009
Location: Tehran, Iran
Posts: 1,123
Blog Entries: 1
Rep Power: 14
nimasam is on a distinguished road
Send a message via Yahoo to nimasam
it's also easy in OpenFOAM, you need to define two inlets as you defines your geometry! give one inlet T1 and the other one T2

There is no hard task here
__________________
Training Course on OpenFOAM at (http://www.isme.ir/)
My Weblog (http://openfoam.blogfa.com/)
nimasam is offline   Reply With Quote

Old   July 31, 2013, 04:45
Default
  #11
Member
 
Vishal
Join Date: Jul 2013
Posts: 73
Rep Power: 4
inf.vish is on a distinguished road
I did that. But that boundary condition just implies that the two inlets are at T1 and T2. It does not imply that the fluid entering them is at T1 and T2.
inf.vish is offline   Reply With Quote

Old   July 31, 2013, 04:55
Default
  #12
Senior Member
 
Nima Sam
Join Date: Sep 2009
Location: Tehran, Iran
Posts: 1,123
Blog Entries: 1
Rep Power: 14
nimasam is on a distinguished road
Send a message via Yahoo to nimasam
its an well-known elbow mixing problem, you can see at picture (temperature contour) that two hot and cold waters are mixing together here!
i used buoyantBoussinesqSimpleFoam! for this problem. so i did not get what the problem is. when you assign a fixed temperature at inlet you force the solver to consider the inlet fluid with that temperature , i dont understand why do u separate them
Attached Images
File Type: png 1.png (20.8 KB, 13 views)
__________________
Training Course on OpenFOAM at (http://www.isme.ir/)
My Weblog (http://openfoam.blogfa.com/)
nimasam is offline   Reply With Quote

Old   July 31, 2013, 04:58
Default
  #13
Member
 
Vishal
Join Date: Jul 2013
Posts: 73
Rep Power: 4
inf.vish is on a distinguished road
Okay. Thanks. I didn't know how OpenFOAM was treating that particular temperature boundary condition. I was thinking it as a Heater kept at the inlet, sort of a film of heat.

Thanks once again

can you share your boundary conditions for p,U,p_rgh and T. I am a bit confused on p_rgh and p.
inf.vish is offline   Reply With Quote

Old   July 31, 2013, 08:35
Default
  #14
Senior Member
 
Nima Sam
Join Date: Sep 2009
Location: Tehran, Iran
Posts: 1,123
Blog Entries: 1
Rep Power: 14
nimasam is on a distinguished road
Send a message via Yahoo to nimasam
i suggest you to read the first chapter of userguide and work with some tutorial cases you will find how to assign your BCs

and about
Quote:
p_rgh and p
you need just assign BC for p_rgh which is pressure minus hydrostatic effect, p will be BC write then by solver, for p, BC can be consider as calculated
__________________
Training Course on OpenFOAM at (http://www.isme.ir/)
My Weblog (http://openfoam.blogfa.com/)
nimasam is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
thobois class engineTopoChangerMesh error Peter_600 OpenFOAM 4 August 2, 2014 09:52
Simulating Water Splash Using a Particle System Zi-Wei Chiou Main CFD Forum 0 March 4, 2002 07:33
CFX 5.5 Roued CFX 1 October 2, 2001 16:49
Setting a B.C using UserFortran in 4.3 tokai CFX 10 July 17, 2001 16:25
Error during Solver cfd guy CFX 4 May 8, 2001 06:04


All times are GMT -4. The time now is 18:59.