[Future Science]

I am doing a study for an internship on the re-entry of the Soyuz capsule into the atmosphere.
So far I've been working on Matlab to analize the aerodynamic coefficients, re-entry angles, pitch damping moment, re-entry corridor and speed, g-loads and so on.

Now, since I know the exact shape of the re-entry capsule, I want to make a study on the same topics (or even further, if possible) using Fluent For Catia.

Since I am a beginner in the CFD world, how should I start?
Drawing the shape of the Soyuz on Catia and then start using Fluent for Catia v 5.4.1 is a good move?

For the moment I am following those topics:

- http://www.cfd-online.com/Forums/mai...e-capsule.html
- http://www.cfd-online.com/Forums/mai...ving-body.html
- http://www.cfd-online.com/Forums/ope...-aerofoam.html

But I am looking for additional suggestions and tips on how to start my work, what to do and or what to avoid.

I am looking for your suggestions!

Thanks in advance!

[RenardP]

Hello,

I suppose first you need to check if the chosen solver is capable of solving hypersonic flows, I suppose you will have a Mach number of order ~10 at re-entry. Probably Fluent will do the job, but you have to check in the documentation how (if possible) to set a case for high speed flows.

[Future Science]

Hi, thanks for your prompt answer.
From all the documentation that I've read so far and from a few on-line researches I've found out that Fluent is able to solve Hypersonic flows.

So I think that Fluent for Catia will also be good for those Mach numbers > 10.

[Future Science]

Any other suggestions?
I remind you that in the first stages of the reentry the Mach number is very high, around 30-35 (hypotesis).

[f-w]

I'm not an expert on the topic, but I've covered it in school. Depending on how accurate you want to get, due to high temperatures, oxygen and nitrogen begin to dissociate and then ionize. You can't use your ideal gas model, and must use a real gas model while assuming the flow is chemically reacting.

I was always fascinated with the subject, but never had the time for it. Keep us posted on your progress. Will you be able to share your results?

[Future Science]

Sure I will, if only I knew where to start from!

[f-w]

Check out this artcile:
http://www.fluent.com/about/news/new...pdfs/nl411.pdf

You might be able to request a detailed report from Fluent's marketing team regarding this study.

[mdz]

Originally Posted by Future Science

I am doing a study for an internship on the re-entry of the Soyuz capsule into the atmosphere.
So far I've been working on Matlab to analize the aerodynamic coefficients, re-entry angles, pitch damping moment, re-entry corridor and speed, g-loads and so on.

Now, since I know the exact shape of the re-entry capsule, I want to make a study on the same topics (or even further, if possible) using Fluent For Catia.

Since I am a beginner in the CFD world, how should I start?
Drawing the shape of the Soyuz on Catia and then start using Fluent for Catia v 5.4.1 is a good move?

For the moment I am following those topics:

- http://www.cfd-online.com/Forums/mai...e-capsule.html
- http://www.cfd-online.com/Forums/mai...ving-body.html
- http://www.cfd-online.com/Forums/ope...-aerofoam.html

But I am looking for additional suggestions and tips on how to start my work, what to do and or what to avoid.

I am looking for your suggestions!

Thanks in advance!

Hi ,

Fluent is unable to work with hypersonic flow.
I advaise to use FASTRAN.

You must create your geometry in FASTRAN mesh grid tools. Better to use axi-symmetris 2D simulation.

The boundary layer is very complex in hypersonic, you must at first calculate it and after try to mesh with at least 4 zones.

KR,

mdz

[vinz]

Dear Margarita,

we are a company specialized in consultancy in the hypersonic domain. we are based in the south of france.
I have a question for you: what do you mean by using 4 zones for the meshing? Are you doing NS computations directly or are you using the combination of Euler computation followed by a boundary layer computation?

Regards,

Vincent

[mdz]

Originally Posted by vinz

Dear Margarita,

we are a company specialized in consultancy in the hypersonic domain. we are based in the south of france.
I have a question for you: what do you mean by using 4 zones for the meshing? Are you doing NS computations directly or are you using the combination of Euler computation followed by a boundary layer computation?

Regards,

Vincent

Dear Vincent,

I am expert in CFD. I am also French. I was involved in hypersonic Project when I was working for ESA-ESTEC Project in Holland.
My simulation with Fastran was validated by experimental data for many space probes with Mach number from 8 to 60 as well for Earth and Planetary re-entry.

So, I suppose, that my meshgrid is correct. This meshgrid method was developped in collaboration with Hypersonic EXPERT from NASA.

I am also was involved in development inhome hypersonic code, but the meshgrid was still the same.

I am sorry, but it bit confidential, so i can't give you more details.

Good luck !

It ver exciting topic, but very difficult...


Best regards, cordialement,

Margarita.