|
[Sponsors] |
September 22, 2011, 16:57 |
Transition Models Help
|
#1 |
New Member
Paul Nardone
Join Date: Sep 2011
Location: Lawrence KS
Posts: 3
Rep Power: 15 |
hello folks out there in cd-adapco land.
My name is Paul and I'm working on my graduate research project. The basic Idea behind this project is to model "Bypass" transition along a flat plate (the plate being similar to a turbine blade). I know there are 2 transition models in the Star-CCM+ product which are 1. The Gamma Re-Theta model, and 2. The Turbulence Suppression model. Does anyone have any advice on which of these to use or are they both useless for this case since such a transition is not typical. (hence why we are studying it). I'm able to get them both to work but I'm not sure if they are outputting the correct answers yet. Beyond this if any one out there has experience with modeling Transition especially "bypass" transition feel free to contact me with information. thank you Paul Nardone Jr University of Idaho, Idaho Falls Nuclear Engineering Department paulnardonejr@gmail.com |
|
September 22, 2011, 18:45 |
|
#2 |
Senior Member
Join Date: Oct 2009
Location: Germany
Posts: 636
Rep Power: 22 |
I'm not sure what you mean by "Bypass transition". But for the Gamm Re Theta model, you will need a huge number of prism layers.
Regarding to the user guide, the turbulence suppresion model is not a true transition model: "The Turbulence Suppression model allows the user to mimic the effect of transition by suppressing the turbulence in a certain pre-defined region. Since it does not have a predictive capability, it is arguably not a true transition model." Should be self-explaining. |
|
September 22, 2011, 20:16 |
|
#3 |
New Member
Paul Nardone
Join Date: Sep 2011
Location: Lawrence KS
Posts: 3
Rep Power: 15 |
Hey thanks for your response. I assumed that the turb. suppression was no good as you mentioned because it wasn't a true transition model.
I'm currently running a Gamma Re Theta model and I did apply a more significant prism layer... 30 layers over a 2 cm boundry layer with a 1.2 cell growth rate. I'm running my model locally with 8-gigs or ram so I didnt want to go too crazy with the mesh (700,000 cells currently)... but my solution blew up... so I think I need to adapt my mesh and a few other parameters. when I said "bypass" transition I meant that transition from a laminar to turbulent state is prematurely onset primarily due to strong free stream turbulence... it's definitely a doosie of a problem for me thanks again for your response and if you have any more advice on the matter I'll definitely take it into consideration Paul |
|
Tags |
bypass, model, transition |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Transition Turbulence Models | Apurva | Main CFD Forum | 3 | September 7, 2018 06:48 |
Ansys 12, Fluent, SST Transition models | bugra | FLUENT | 9 | February 8, 2016 02:57 |
Issue with transition models | k.vimalakanthan | CFX | 1 | April 26, 2011 23:15 |
Fluent 12.1 - transition viscous models | kdrbrk | FLUENT | 4 | July 29, 2010 12:34 |
Code release: Flow Transition and Turbulence | Chaoqun Liu | Main CFD Forum | 0 | September 26, 2008 18:15 |