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Old   August 1, 2005, 21:50
Default Negative Pressure
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Kevin
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In calculating the converging-diverging supersonic nozzle with the FINE/Turbo, the NEGATIVE pressure or density in domain comes so often during iterations finally ending up with a crash. Total pressure and temperature with flow angles were given at the inlet boundary, and static pressure was given in the outlet boundary when subsonic. The CFL number has been lowered up to 0.01 but in no use. Anyone with a better idea, please ?
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Old   August 5, 2005, 12:20
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Just a guess
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Are you sure of your boundary conditions, i.e. that the static pressure at outlet is lower than the total pressure at inlet ?
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Old   August 10, 2005, 04:54
Default Re: Negative Pressure
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Kevin
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Of course. 7 bar pressure at inlet and atmosphere at exit are applied to the impulse turbine stage.
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Old   August 12, 2005, 03:27
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sffsa
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hfhdfd
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Old   September 21, 2005, 18:51
Default Re: Negative Pressure
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ing
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If you are using the fine turbo upwind scheme this isn't surprising. There are major errors in the implementation.
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Old   January 9, 2006, 00:22
Default Re: Negative Pressure
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rupesh
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hi

Just check the operating pressure what you given . if u specified Pr. there just make it zero. while definig inlet Pr. make gauge pr. as 101325 and defaine ur inlet pr. and the outlet pr. must be less than inlet pr.
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