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

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Old   May 21, 2004, 07:32
Default TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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USERPH
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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
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Old   May 21, 2004, 09:09
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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STK, Just relax! Take it easy and try to read the PHOENICS documentation. ;-)
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Old   May 21, 2004, 09:34
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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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.
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Old   May 21, 2004, 20:07
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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userph
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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.
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Old   May 23, 2004, 10:08
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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AEROFUN
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I HAVE THE SAME PROBLEMS!!!!!!! I DO NOT CONSIDER PHOENICS A RELIABLE CFD SUPERSONIC SOLVER, WHAT DOES CHAM SAY ABOUT IT?
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Old   May 23, 2004, 20:32
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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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.
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Old   May 24, 2004, 04:46
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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AEROFUN
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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??????????????
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Old   May 25, 2004, 12:02
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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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.
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Old   July 13, 2004, 17:55
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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George
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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??????????????
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Old   April 3, 2005, 15:07
Default Re: TO CHAM.HOW I SET UP AN EASY SUPERSONIC CASE?
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PattiMichelle
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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
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