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

Choosing model for plume into stratified pond.

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 13, 2012, 16:48
Default Choosing model for plume into stratified pond.
  #1
New Member
 
Simon
Join Date: Dec 2012
Location: Colorado
Posts: 16
Rep Power: 4
Roark is on a distinguished road
I am trying to decide on a model to use. The goal of the project is to model the change in stratification in a pond when warm water is injected as a jet. It is important that buoyancy effects and the jet are accurately modeled but I want to know long term (order days, not weeks) influences on pond stratification.

I initially though about using Fluent, but the period of interest is of order days while inflow duration is of order hours. I think the timesteps constraints will make using Fluent not unfeasible.

I am only interested in vertical dynamics so a 2D-model is fine. CE-QUAL-W2 is a laterally averaged 2D model for environmental purposes and is designed for longer time scales. I may be able to crank up the resolution and try to model the inflow, but I am not sure if this is appropriate.

Does anybody have any advice on what model to select for this project? Words of wisdom will be greatly appreciated!
Roark is offline   Reply With Quote

Old   December 13, 2012, 17:33
Default
  #2
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 1,588
Rep Power: 20
FMDenaro will become famous soon enough
Quote:
Originally Posted by Roark View Post
I am trying to decide on a model to use. The goal of the project is to model the change in stratification in a pond when warm water is injected as a jet. It is important that buoyancy effects and the jet are accurately modeled but I want to know long term (order days, not weeks) influences on pond stratification.

I initially though about using Fluent, but the period of interest is of order days while inflow duration is of order hours. I think the timesteps constraints will make using Fluent not unfeasible.

I am only interested in vertical dynamics so a 2D-model is fine. CE-QUAL-W2 is a laterally averaged 2D model for environmental purposes and is designed for longer time scales. I may be able to crank up the resolution and try to model the inflow, but I am not sure if this is appropriate.

Does anybody have any advice on what model to select for this project? Words of wisdom will be greatly appreciated!

I am not sure to understand your flow problem... I assume the flow is turbulent, isn't it? So, are you sure the 2D RANS makes sense?

However, I worked on buoyancy-induced flow but using LES, may you can find some help in the references cited in:

- Ocean Modelling, Vol. 17, pp. 199-218 (2007)
- http://link.springer.com/article/10....162-010-0202-x
FMDenaro is offline   Reply With Quote

Old   December 13, 2012, 18:13
Default
  #3
New Member
 
Simon
Join Date: Dec 2012
Location: Colorado
Posts: 16
Rep Power: 4
Roark is on a distinguished road
Thanks Filippo,

That is cool work, but I don't think I need that much detail! I need to investigate how the lake stratifies, generally. LES is way too computationally expensive for this purpose. RANS should do just fine. I am not sure though if the 2D approach is appropriate.
Roark is offline   Reply With Quote

Old   December 13, 2012, 18:25
Default
  #4
New Member
 
Simon
Join Date: Dec 2012
Location: Colorado
Posts: 16
Rep Power: 4
Roark is on a distinguished road
Maybe there is an ocean-type model which will work. Any ideas?
Roark is offline   Reply With Quote

Old   December 13, 2012, 18:36
Default
  #5
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 1,588
Rep Power: 20
FMDenaro will become famous soon enough
Quote:
Originally Posted by Roark View Post
Maybe there is an ocean-type model which will work. Any ideas?
yes, there are some models that focuses on the vertical prevalence of the flow, you should try to get the lectures at CISM in 2004
FMDenaro is offline   Reply With Quote

Old   December 13, 2012, 18:38
Default
  #6
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 1,588
Rep Power: 20
FMDenaro will become famous soon enough
also, one of my collegues worked on flow in lakes, see the references
http://www.szn.it/SZNWeb/cmd/ShowArc...=HUMANRESOURCE
FMDenaro is offline   Reply With Quote

Old   December 13, 2012, 20:17
Default
  #7
New Member
 
Simon
Join Date: Dec 2012
Location: Colorado
Posts: 16
Rep Power: 4
Roark is on a distinguished road
I guess I can't rule Flow-3D out either. But I am still concerned that Flow-3D and Fluent are not appropriate for a multi-day simulation.
Roark is offline   Reply With Quote

Reply

Tags
model selection, stratified flow, two-dimensions

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
Atomization and Breakup model xck1986 OpenFOAM 4 May 31, 2014 04:43
multiphaseInterFoam for RAS turbulence model chiven OpenFOAM Bugs 7 August 23, 2011 02:52
Help with choosing a viscosity model xTamx420 FLUENT 5 July 4, 2011 17:09
help for different between les model (subgrid-scale model) liuyuxuan FLUENT 1 October 2, 2009 15:25
2 stage axial turbine model convergence issues sherifkadry CFX 2 September 7, 2009 20:51


All times are GMT -4. The time now is 21:16.