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Backflow in nozzle exit (combustion chamber with nozzle) |
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#1 |
New Member
Lee Jo
Join Date: Mar 2020
Posts: 29
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Hi..
I'm modelling a 3d combustion chamber with nozzle...the operating pressure are very high and fuels used are CH4 and liquid Oxygen (cryogenic temperature) Inlets : 8MPa Outlet : tried both 0MPa and 101325 Pa Operating conditions: 6MPa I am getting backflow in the outlet and the setup diverges...my mesh is good and have no skewness at exit or inside chamber and nozzle..my mesh is fine.. I even tried long slender gradually increasing length mesh at outlet so that the backflows stop.. My outlet pressure outlet backflow specification: Normal to boundary... Anyone knows how to solve this...??!! |
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#2 |
Senior Member
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It appears to be a compressible flow. Use value of 0 Pa as operating pressure and apply all boundary pressure values as absolute values. You may also want to choose non-reflecting condition at the outlet.
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Regards, Vinerm PM to be used if and only if you do not want something to be shared publicly. PM is considered to be of the least priority. |
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#3 |
New Member
Lee Jo
Join Date: Mar 2020
Posts: 29
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Yeah..I'm using SRK real gas equations..my outlet is a pressure outlet and how do I set it as a non reflecting condition??
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#4 |
Senior Member
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That option is available within boundary condition panel. Open pressure outlet and you will see Acoustic condition options.
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Regards, Vinerm PM to be used if and only if you do not want something to be shared publicly. PM is considered to be of the least priority. |
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