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

Microchannels Reactor

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

Reply
 
LinkBack Thread Tools Display Modes
Old   March 4, 2013, 13:39
Default Microchannels Reactor
  #1
New Member
 
Joana Andrade
Join Date: Feb 2013
Posts: 5
Rep Power: 4
JoanaAndrade is on a distinguished road
Hello!
I'm new in CFX and I have to model a microchannel reactor. It has an cylindrical inlet (7,2 mm diameter) connected with a cubic part (10 mm side). From this cubic part to the outlet (that is symmetrical) there are a lot of microchannels (1mm side). After setting up, when I'm gonna see the results, there is no way the flow goes through the microchannels.
Can someone help me?
JoanaAndrade is offline   Reply With Quote

Old   March 4, 2013, 17:26
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,652
Rep Power: 84
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
Please post an image of what you are modelling, and some details about the fluid and boundary conditions.
ghorrocks is offline   Reply With Quote

Old   March 6, 2013, 13:55
Default
  #3
New Member
 
Joana Andrade
Join Date: Feb 2013
Posts: 5
Rep Power: 4
JoanaAndrade is on a distinguished road
It is like that. First, I'm trying to make a water flow. In the inlet, the flow rate range is between 0.25 and 250 g/min. In the outlet, relative pressure = 0.
Attached Images
File Type: jpg IMAGEM.jpg (20.0 KB, 11 views)
JoanaAndrade is offline   Reply With Quote

Old   March 6, 2013, 18:15
Default
  #4
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,652
Rep Power: 84
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
Is it correct that one fluid flows through the orange channels and another through the blue channels and they cannot mix? If so then this is a trivial flow to model. There will be something simple wrong with your set up. If it is more complex then this please explain in more detail.
ghorrocks is offline   Reply With Quote

Old   March 7, 2013, 15:05
Default
  #5
New Member
 
Joana Andrade
Join Date: Feb 2013
Posts: 5
Rep Power: 4
JoanaAndrade is on a distinguished road
Yes, they cannot mix. I know it seems trivial, but the fluids just don't go through the channels. It goes like that. The set up is very simple, It's just water and air, no heating. And I've already increased the flow rate, and it was just the same. I'm wondering if there something wrong with meshing. I've just generate the standard mesh, no changes.
Attached Images
File Type: jpg Sem título.jpg (49.0 KB, 11 views)
JoanaAndrade is offline   Reply With Quote

Old   March 7, 2013, 17:20
Default
  #6
Senior Member
 
Erik
Join Date: Feb 2011
Location: Earth (Land portion)
Posts: 486
Rep Power: 9
evcelica is on a distinguished road
Looks like it goes through the channels to me? Inlets are on the top and the left? Maybe you think it doesn't because the streamline don't go all the way through? That doesn't mean the flow stopped.
evcelica is offline   Reply With Quote

Old   March 11, 2013, 11:55
Default
  #7
New Member
 
Joana Andrade
Join Date: Feb 2013
Posts: 5
Rep Power: 4
JoanaAndrade is on a distinguished road
Really? I tought so... And how do I know it is ok? Isn't the streamlines supposed to show the way the flow travels?
JoanaAndrade is offline   Reply With Quote

Old   March 11, 2013, 16:09
Default
  #8
Senior Member
 
OJ
Join Date: Apr 2012
Location: United Kindom
Posts: 475
Rep Power: 11
oj.bulmer will become famous soon enough
If I am not missing something, this seems perfectly normal. If you have fully converged the solution, what is the domain imbalance for both the fluids? If it is less than (at least) 1% it should be alright. For better results, I would run till the domain imbalances are less than 0.01%, if it can be afforded.

OJ
oj.bulmer is offline   Reply With Quote

Old   March 11, 2013, 17:38
Default
  #9
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,652
Rep Power: 84
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
Yes, the streamlines show the flow travel. But they are numerically integrated over the solution dataset and therefore are approximations. When you have long thin channels they do tend to wander a little and if they hit a wall they will stop.
ghorrocks 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
transient result in spray reactor with swirl flow glenn creten Main CFD Forum 1 August 14, 2012 05:10
Fixed bed reactor.....you can help...I am sure!! Amrrefay FLUENT 0 June 6, 2009 06:58
Phosphoric acid reactor model N.Ramakrishnan Main CFD Forum 0 July 29, 2004 06:38
Passive cooling system for batch reactor Darek Main CFD Forum 0 September 30, 2003 05:06
DAF reactor model( willyban FLUENT 0 May 9, 2001 04:26


All times are GMT -4. The time now is 14:10.