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

Stratified environment

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 19, 2012, 01:44
Exclamation Stratified environment
  #1
HMR
Member
 
HMR
Join Date: Jan 2011
Posts: 31
Rep Power: 15
HMR is on a distinguished road
Hi CFX Users,

I am simulating a case into a small rectangular box(length=width=1m, height=0.3m) open top, wall non-slip rigid insulated and bottom also insulated except the small nozle(r=0.005m) for injecting single phase water jet flow inside it. Newtonian stratified single phase fluid is considered in this box. From calculation, I put water jet velocity0.0343m/s and its temperature 298.64K. As stratified fluid stay in the box so every meter of height of the box temperature will chage N=8.155 K/m so i write an expression To=302.44-N* Z coordinate, and initializes it . Choose bouyancy and its temperature 300K from setup as this is a negative bouyancy case.

mesh sizes 3mm, time step 0.087 with 1.8million of mesh, I run this simulation for 400sec.
Everything fine , simulation finished well but the problem is jet flow penetration height inside this box is not long enough what we expected from previous investigations done by another people in fluent.

I do not understand what is happening. I tried in different way but no solutions i get till now.

If anybody give me any suggestion it will be a great help for me.Because around me knowbody actually know CFX.

Regards

HMR
HMR is offline   Reply With Quote

Old   July 19, 2012, 07:08
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,850
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Can you confirm that your temperature function just defines the intial condition? Obvious from there the air establishes its own temperature field in the simulation.

Have a look at this FAQ: http://www.cfd-online.com/Wiki/Ansys..._inaccurate.3F
ghorrocks is offline   Reply With Quote

Old   July 21, 2012, 22:07
Default
  #3
HMR
Member
 
HMR
Join Date: Jan 2011
Posts: 31
Rep Power: 15
HMR is on a distinguished road
Hi Glenn,

Thanks for your reply. Yes I am trying to figure out the problem according to your advice.

Cheers

HMR
HMR is offline   Reply With Quote

Old   July 23, 2012, 10:44
Default
  #4
Member
 
Felggv's Avatar
 
Felipe Gobbi
Join Date: Apr 2012
Location: Brazil
Posts: 76
Rep Power: 14
Felggv is on a distinguished road
Attach some pictures of your results so ppl here can analyse.
Felggv is offline   Reply With Quote

Reply


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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Windows Environment variables- to solve problems in compiling UDF in Fluent Modest Cat Fluent UDF and Scheme Programming 39 May 18, 2016 11:33
CFX11 + Fortran compiler ? Mohan CFX 20 March 30, 2011 19:56
BC for Natural Convection in Stratified environment toyoto Main CFD Forum 0 September 3, 2009 00:10
Modelling natural convection in stratified environment toyoto FLUENT 0 September 3, 2009 00:05
cfd simulation between soild & porous environment Latifimran Jalil Main CFD Forum 0 September 12, 2002 19:42


All times are GMT -4. The time now is 13:01.