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Old   March 3, 2008, 12:57
Default phase change
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Robert
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Hello, I would like to simulate a flow, which has phase change, from water to vapor. I use the mixture/cavitation model. I calculate the vaporization pressure with a polynom. I use pressure inlet boundary condition for inflow, and pressure outlet for outflow. The outflow pressure lower, like the vaporization pressure. My problem: The fluent limit the pressure to the vaporization pressure and I don't know, why? If somebody know, please tell it to me

Thanks

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Old   March 5, 2008, 03:42
Default Re: phase change
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Robert
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Please help me, it is very important for me. Thanks
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Old   March 5, 2008, 11:02
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Pavan
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Thanks Robert. It was pretty much what I was doing. I was concerned about the difference I was seeing over flow time. But the error was less than 1.5% That still should not exist but I guess it could be numerical error or something. I guess I won't worry about it.

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Old   March 5, 2008, 11:03
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Pavan
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sorry responded in the wrong section!
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Old   March 7, 2008, 02:03
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Syed Shabbar Raza
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23.6.2 Wet Steam Flow Equations

The wet steam is a mixture of two-phases. The

primary phase is the gaseous-phase

consisting of water-vapor (denoted by the subscript v) while the

secondary phase is the liquid-phase

consisting of condensed-water droplets (denoted by the subscript l).

( and my dear u want to model inverse, i mean here fluent assume that the primary phase is steam, but in your case it is water and i can guess that u have given the boundary condition for water ( inlet condition),

so i think we should use inlet boundary condiition for outlet and vice versa

plz share your view

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Old   March 7, 2008, 07:09
Default Re: phase change
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Syed Shabbar Raza
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for using wet vapors fluent have limitation of 273k to 647k, might be your temperature exceed this limits, that why it limits ur pressure
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Old   May 2, 2009, 07:17
Default helpppp
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tuce
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tuce is on a distinguished road
would somebody help me pleasee?I try to simulate two phase flow (water
boiling )by cfd .but I could not manage it.I really need its tutorials.my mail address is tuceyilmaz1984@hotmail.com ıf somebody helps I will be very glad.tnanks by now.
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