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Old   December 12, 2012, 06:56
Default Does Anybody knows what is it?
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Does Anybody knows what is it?

Its Fluents calculation. Jey engines nozzle. 2d axisymmetric model
double precision
density based
k-e SST
there are pessure distribution vibrations
What is the error?
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Old   December 12, 2012, 07:09
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it is a simulation of By pass and core flow ?
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Old   December 12, 2012, 13:44
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Quote:
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it is a simulation of By pass and core flow ?
Yes, It's a simulation of Turbofan Engines nozzle
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Old   December 12, 2012, 14:01
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Yes, It's a simulation of Turbofan Engines nozzle
I dont know how to get rid of these pseudo little unphysical shock waves
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Old   December 13, 2012, 03:38
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could it be because of limiter type?
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Old   December 15, 2012, 03:10
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How did you model the bypass and core flow?

Will they form the one stream when exiting the domain? Do you have convergent nozzle after the bypass and core flow?

How did you specify the boundary conditions for the core flow and bypass flow?

What is the boundary condition at the outlet of the domain?

Mesh information : mesh type, no of nodes and refinement in the critical areas?

Convergence criteria?

Turbulence model?

Approximation in geometry?

How did you model the mixing?

Please post few pics with mesh, domain etc to clearly see the problem area and then appropriate solution!!!
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Old   December 15, 2012, 08:02
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Boundary conditions in Bypass and Core channels where Pressure Inlet ( Total Pressure and Total temperature)
in the outlet of the domain - pressure outlet (static pressure)
convergence criteria - all forces on the nozzle are constant and global disbalances
Turbulence model - k-omega-SST
What do u means about aproximations in geometry?
Mesh - hexa
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Old   December 15, 2012, 09:41
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It is mixed type turbofan engine?

I am assuming you have three streams. First one is freestream, second one is bypass and below one is the core flow. Right?

Are they going to mix first and then exit from the propelling nozzle?

PS: I have done the mixed flow turbofan simulation successfully in past
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Old   December 15, 2012, 09:43
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Quote:
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It is mixed type turbofan engine?

I am assuming you have three streams. First one is freestream, second one is bypass and below one is the core flow. Right?

Are they going to mix first and then exit from the propelling nozzle?
No, It's separated flow nozzle
two streams - core and fan
and external flow with Mach number 0.8
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Old   December 15, 2012, 09:53
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Normal result of calculation - shock waves in fan stream without ripples near shock waves
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Old   December 16, 2012, 12:56
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No one knows)
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Old   December 16, 2012, 14:05
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I checked your mesh and it looks fine and every thing else looks ok also. Can you send the files?
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Old   December 16, 2012, 22:13
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I checked your mesh and it looks fine and every thing else looks ok also. Can you send the files?
Where can I send you files?
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Old   December 17, 2012, 23:54
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Quote:
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I checked your mesh and it looks fine and every thing else looks ok also. Can you send the files?
I have send you an email with result files
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