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

TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   May 21, 2004, 07:32
Default TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #1
USERPH
Guest
 
Posts: n/a
TO COMPANY CHAM

I WANT TO SIMULATE SUPERSONIC FLOW, BUT I CAN'T SEE ANY RIGHT TUTORIAL (Y101 AND 105 ARE TOTALLY WRONG!) HOW I SOLVE HYPERBOLIC EQUATIONS? THANKS
  Reply With Quote

Old   May 21, 2004, 09:09
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #2
Another User
Guest
 
Posts: n/a
STK, Just relax! Take it easy and try to read the PHOENICS documentation. ;-)
  Reply With Quote

Old   May 21, 2004, 09:34
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #3
Another User
Guest
 
Posts: n/a
If you like supersoninc cases try 158,159,156,160,161,908 Parabolic? May be 170,171,172,176,173,174,175 (and more..) If you do not understand something, it's not reason to said bad things.
  Reply With Quote

Old   May 21, 2004, 20:07
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #4
userph
Guest
 
Posts: n/a
have you seen these cases, i insist saying bad things because for example in case 159, the inlet velocity is 2 meters pers second (and the others are not right f.e. underexpansion..)! i think is an example case and it must be represantative for that kind of flows. I checked and ground there is no code! i don't know what is happening, but i am going to learn soon! thanks for your help for the cases.
  Reply With Quote

Old   May 23, 2004, 10:08
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #5
AEROFUN
Guest
 
Posts: n/a
I HAVE THE SAME PROBLEMS!!!!!!! I DO NOT CONSIDER PHOENICS A RELIABLE CFD SUPERSONIC SOLVER, WHAT DOES CHAM SAY ABOUT IT?
  Reply With Quote

Old   May 23, 2004, 20:32
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #6
Another User
Guest
 
Posts: n/a
Why? Please, say something concrete, not like "I KNOW AT LEAST 70%" and "LOUGH UNTIL TOMORROW". It's not scientific words. Please, just calculations and numbers but not "I think this picture is incorrect because I didn't see shock waves". If you will write in same style, nobody answer on your questions.
  Reply With Quote

Old   May 24, 2004, 04:46
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #7
AEROFUN
Guest
 
Posts: n/a
I DON'T KNOW TO WHOM YOU ARE POSTING, BECAUSE I DIDN'T TELL ANYTHING LIKE THOSE YOU MENTIONED. ANYWAY YOU HAVE TO KNOW IF A PROCESS LIKE A SHOCK DOESN'T APPEAR IN THE FLOWFIELD, WHEN IT HAS TO BE SHOWN, THEN THE CODE IS TOTALLY INACCURATE. I MEAN THAT SHOCK IS A VERY MAIN PHENOMENON. AND I EXPLAIN: WHEN A SUPERSONIC FLOW ENTERS IN A CONVERGING NOZZLE , BECAUSE OF THE DEFLECTION ANGLE, ARE FORMED SHOCK WAVES. THESE ARE REGIONS OF DISCONTINUITY (jump of pressure, fall of mach number e.t.c). WHEN I RUN THESE LIBRARY CASES I SAW THAT THE FLOW RESSEMBLES TO THE LAMINAR SUBSONIC FLOW, WITHOUT ANY PROCESS RELATIVE TO SUPERSONIC. ALSO SEE THE PROBLEMS ARISING IN VR-VIEWER AFTER RUNNING EARTH. THE FULL GRID DOESN'T APPEAR. THE ONLY EXAMPLE THAT IS RIGHT IS IN POLIS IN THE SECTION OF MATHEMATICAL-PHYSICAL CONTENT OF PHOENICS, WHICH IS NOT AVAILABLE IN THE LIBRARY (NOT ANY Q1 AND SET UP). THIS DOESN'T CREATE DOUBTS ABOUT HYPERBOLIC SOLVING??????????????
  Reply With Quote

Old   May 25, 2004, 12:02
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #8
Supersonic user
Guest
 
Posts: n/a
Try running library case 156; supersonic flow in a duct using the hyperbolic solver (so only a single sweep in marching direction is required for the solution). Run it via the Satellite. The results are correct; both the expansion and compression waves are of the right strength. I agree that cases Y101 and Y105, which uses the elliptic solver, are incorrect. However, I note that they use fine-grid embedding, and I would suggest eliminating the fine-grid embedding, in case that is responsible for the spurious solutions.
  Reply With Quote

Old   July 13, 2004, 17:55
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #9
George
Guest
 
Posts: n/a
I DON'T KNOW TO WHOM YOU ARE POSTING, BECAUSE I DIDN'T TELL ANYTHING LIKE THOSE YOU MENTIONED. ANYWAY YOU HAVE TO KNOW IF A PROCESS LIKE A SHOCK DOESN'T APPEAR IN THE FLOWFIELD, WHEN IT HAS TO BE SHOWN, THEN THE CODE IS TOTALLY INACCURATE. I MEAN THAT SHOCK IS A VERY MAIN PHENOMENON. AND I EXPLAIN: WHEN A SUPERSONIC FLOW ENTERS IN A CONVERGING. NOZZLE , BECAUSE OF THE DEFLECTION ANGLE, ARE FORMED SHOCK WAVES. THESE ARE REGIONS OF DISCONTINUITY (jump of pressure, fall of mach number e.t.c). WHEN I RUN. THESE LIBRARY CASES I SAW THAT THE FLOW. RESSEMBLES TO THE LAMINAR SUBSONIC FLOW, WITHOUT ANY PROCESS RELATIVE TO SUPERSONIC. ALSO SEE THE PROBLEMS ARISING HTTP://WWW.HANDYMATE.CO.UK IN VR-VIEWER AFTER RUNNING EARTH. THE FULL GRID DOESN'T APPEAR. THE ONLY EXAMPLE THAT IS RIGHT IS IN POLIS IN THE SECTION OF MATHEMATICAL-PHYSICAL CONTENT OF PHOENICS, WHICH IS NOT AVAILABLE IN THE LIBRARY (NOT ANY Q1 AND SET UP). THIS DOESN'T CREATE DOUBTS ABOUT HYPERBOLIC SOLVING??????????????
  Reply With Quote

Old   April 3, 2005, 15:07
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
  #10
PattiMichelle
Guest
 
Posts: n/a
Hi Supersonic User - I would like to play around with supersonic flows. I have been playing a LOT with VR-case 808 (flow around a circular cylinder). Can you suggest what changes I would make to get accurate results of a supersonic flow, i.e., what models do I invoke? Air-isentropic flow (versions 1 or 2)? What turbulence model? Is there some other model or solver that that needs to be set to correctly handle MACHno > 1?

THANKS!!! PattiMichelle
  Reply With Quote

Reply

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
Hi CHAM, R U Worried? A Worried Phoenics User Phoenics 2 July 12, 2007 02:26
looking for a test case, DES, Supersonic flow kaarthik Main CFD Forum 0 June 7, 2007 05:49
CHAM - Search on Polis Mark Russell Phoenics 3 September 13, 2001 07:30
Suggestion to CHAM Zeng Phoenics 13 April 9, 2001 04:52
CHAM and simuserve.com websites down? Sam Matson Phoenics 1 January 16, 2001 04:54


All times are GMT -4. The time now is 02:50.