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compressible flow solver in OF1.6

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Old   April 28, 2010, 09:33
Question compressible flow solver in OF1.6
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Hi all,

Why PISO & SIMPLE algorithms are used in OF for compressible flow problems. These algorithms are for pressure linked equation i.e. incompressible flows and for low Mach no flows.
Even density based solver "rhoSonicFoam" uses PISO algorithm why?

In compressible flows computation, we solve momentum equation to get velocity, energy equation to get temperature, density from continuity equation and pressure from perfect gas equation. correct me if i am wrong.
If this is the case, then why PISO & SIMPLE come into picture.

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mecbe
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Old   April 29, 2010, 11:04
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Ngoc-Minh Truong
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You'll find some answers here:
OF Compressible equations SIMPLE/PISO

Enjoy
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Old   April 29, 2010, 12:52
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Hi,

I read the thread and it was mentioned that steady state problem has to be solved by Pseudo Transient for stability. Can you give some details on it, because i am in the process of converting the "rhoSonicFoam" inviscid density based transient compressible flow solver(this doesn't uses PISO algorithm).

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Old   April 30, 2010, 01:07
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Please, define the problem you want to solve, or we cannot give any specific answer. What is the Mach number, for example?

In addition, what do you mean with "converting" rhoSonicFoam? It is already a transient solver, and it doesn't use the PISO algorithm because it is density based.

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Old   April 30, 2010, 01:17
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Hi Alberto,

I want to solve transonic & supersonic inviscid steady flow over missile.
Mach No -0.9,1.2,1.8 & 2.5.

I saw the "rhoSonicFoam" code, it doesnt uses PISO algorithm, but in tutorial case file, it was there. sorry for that.

I want to convert it to steady state solver, bcz transient solver takes lot of time to converge.

One more question, can you explain about the slip boundary condition (other than given in the user guide).

Also, i want to implement some more inviscid flux discretization schemes like AUSM, HLLC.. Can you give some advice on how to carry on.

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Old   April 30, 2010, 01:40
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Quote:
Originally Posted by mecbe2002 View Post
Hi Alberto,

I want to solve transonic & supersonic inviscid steady flow over missile.
Mach No -0.9,1.2,1.8 & 2.5.

I saw the "rhoSonicFoam" code, it doesnt uses PISO algorithm, but in tutorial case file, it was there. sorry for that.

I want to convert it to steady state solver, bcz transient solver takes lot of time to converge.
You might want to take a look also to rhoCentralFoam and rhopSonicFoam.

Quote:
One more question, can you explain about the slip boundary condition (other than given in the user guide).
What is not clear?

Best,
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Old   April 30, 2010, 02:37
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I will look into those two schemes.

What about implementing new inviscid flux computation schemes like AUSM, HLLC.

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Old   April 30, 2010, 12:06
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Quote:
Originally Posted by mecbe2002 View Post
I will look into those two schemes.

What about implementing new inviscid flux computation schemes like AUSM, HLLC.

thanks
mecbe
There's quite some work to do to be able to implement those. You might want to take a look at aeroFoam:

New densitybased solver AeroFoam

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Old   April 30, 2010, 12:50
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Hi Alberto,

Thanks for the thread. I downloaded the solver.
This will help a lot for my work.

thanks
mecbe
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Old   December 25, 2010, 10:17
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Hi mecbe,
Please reply with AeroFOAM (its written for OF V 1.4.1) compatibility problem in OF V 1.6 + .
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