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

Supersonic impinging Jet in vacuum

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   February 23, 2024, 11:20
Default Supersonic impinging Jet in vacuum
  #1
New Member
 
Jannis
Join Date: Sep 2022
Posts: 7
Rep Power: 3
turbvisc is on a distinguished road
Hello,


I'm trying to run a simulation on the Plume-Surface-Interaction in a lunar environment. However the simulation keeps diverging. The total pressure and Mach number are increasing very much in one cell near the outlet (either on the outlet near the ground or near the outer nozzle wall, see picture 2). I have tried various approaches with fully structured and unstructured meshes, both fine and coarse, or coarsening towards the outlets, with resolved or unresolved boundary layers.

I achieved on result on a relativly coarse mesh (see picture 1), but refining, again, leads to divergence.
Also I varied the size of the farfield, without achieving something.



Boundaries:
Pressure Inlet: 4.5 MPa, ~2700 K

Outlet: 1 Pa, Non Reflective Wave Model with Pressure at infinity
No slip walls



Solver settings:
steady state, axissymmetric

species transport
k-w-SST, with Produciton Limiter and Compressibility Effects

Solver: density based, implicit

Flux: AUSM
Discretization: Least Squares Cell Based, second order (also tried with first order)
Higher Order Term Relaxation enabled
CFL and URF: 0.3


hybrid and fmg initialization



I am aware, that the Navier-Stokes equations are only valid for a continuum, this simulation shall be used, to identify the continuum breakdown, to then couple with a DSMC sim. Even though potentially unphysical, literature has shown, that fluent could be used to run such a case (e.g. https://www.researchgate.net/publica..._lunar_landing or https://www.semanticscholar.org/pape...0bc82cc29da622)


Ma_number.png

diverged.png
turbvisc is offline   Reply With Quote

Reply

Tags
compressible, divergence, nozzle, supersonic, vacuum

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Supersonic Overexpanded Impinging jet - Convergence issue Guillaume Crn FLUENT 1 February 5, 2022 21:40
wall heating by supersonic impinging jet xkang FLUENT 3 February 8, 2015 05:29
SUPERSONIC IMPINGING JET shuo Main CFD Forum 0 February 12, 2009 03:56
supersonic jet into vacuum lee FLUENT 0 March 27, 2007 09:54
IMPINGING JET ........... HELP!!!!!!!! Amir Omoumi Main CFD Forum 10 August 30, 1999 22:11


All times are GMT -4. The time now is 10:49.