|
[Sponsors] |
April 19, 2013, 16:41 |
Hypersonic flow over double wedge
|
#1 |
New Member
Join Date: Apr 2013
Posts: 5
Rep Power: 13 |
Hi! I want to analyze the shock interactions in a hypersonic flow over a double wedge. My Mach number is 9. I generated an unstructured mesh with about 2lakh elements. I chose such a large number because my instructor says that the mesh has to be very refined for such flows.I am new to CFD and Fluent and I am not sure in how many iterations my solution should converge. I set the residuals to 1e-5. Even after about 80000 iterations, the residual was still at 1e-2. Is this natural or am I doing something wrong? Also, how long do these computations usually take? Please help. Thanks a lot.
|
|
April 19, 2013, 17:34 |
|
#3 |
New Member
Join Date: Apr 2013
Posts: 5
Rep Power: 13 |
I could not get any tutorial specific to double wedge flow problems. But, I followed a tutorial on supersonic flow over a wedge. I think my boundary conditions are also right. I have set the wedges to wall boundary condition, otlet to pressure outlet and the farfield boundary to pressure farfield. As far as the mesh is concerned, I perform the grid check operation whenever I start the simulation. It has never shown any error.
|
|
April 19, 2013, 17:50 |
|
#4 |
Super Moderator
Ghazlani M. Ali
Join Date: May 2011
Location: Tokyo, Japan
Posts: 1,385
Blog Entries: 23
Rep Power: 29 |
good, how about your mesh ? are working in 3d or 2D ?? structured or unstructured ? i have work with supersonic flow, they are very very difficult to converge, did you run the simulation with 1st order then switched to second ?
|
|
April 19, 2013, 17:56 |
|
#5 |
New Member
Join Date: Apr 2013
Posts: 5
Rep Power: 13 |
It is a 2D mesh. and a very simple geometry. It is an unstructured mesh with local refining around a vertex. I directly ran it in the second order.
Last edited by marilyn; April 19, 2013 at 18:05. Reason: more info |
|
April 19, 2013, 18:04 |
|
#6 |
Super Moderator
Ghazlani M. Ali
Join Date: May 2011
Location: Tokyo, Japan
Posts: 1,385
Blog Entries: 23
Rep Power: 29 |
deciding what order should depend on the nature of the flow, and not the simplicity of the geometry. hypersonic should be difficult to predict. i suggest you start with a density based, first order see what you get...
|
|
April 19, 2013, 18:07 |
|
#7 |
New Member
Join Date: Apr 2013
Posts: 5
Rep Power: 13 |
shall try doing that and see what happens. thanks a lot for your help
|
|
April 20, 2013, 15:26 |
|
#8 |
Senior Member
|
||
Tags |
hypersonic, wedge |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
About Some Concepts:Laminar flow, turbulent flow, steady flow and time-dependent flow | Jing | Main CFD Forum | 8 | October 5, 2018 18:02 |
Hypersonic flow over a wedge | Ravenn | FLUENT | 6 | March 7, 2013 08:12 |
Errorneous velocity near walls while using wedge type BC for axisymmetric flow | diwakaranant | OpenFOAM Running, Solving & CFD | 0 | February 9, 2013 01:41 |
Hypersonic flow scramjet | ishaninair | OpenFOAM Running, Solving & CFD | 0 | March 10, 2011 08:45 |
what's wrong about my code for 2d burgers equation | morxio | Main CFD Forum | 3 | April 27, 2007 11:38 |