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January 19, 2012, 14:08 |
Gravity in vertical pipe
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#1 |
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Hello,
does someone know how to run Fluent simulation of a vertical pipe with gravity on? I don't see any difference in the flow when gravity is enabled... Many thanks |
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January 20, 2012, 00:57 |
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#2 |
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Could you provide more details, like your BC's and fluid used, single or multi phase.
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January 20, 2012, 03:07 |
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#3 | |
Senior Member
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Quote:
If you don't have pressure BC in incompressible flow fields, including gravity doesn't change the flow field; because you can introduce new pressure variable numerically which includes the gravity term. Obviously, you can find the original pressure field by excluding the added field. Bests,
__________________
Amir |
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January 20, 2012, 03:45 |
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#4 |
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If you want to see effect of hydrostatic pressure, which depends on gravity, in a pressure field try set the operating density to zero (Cell zone conditions -> Operating conditions -> Specified operating density).
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January 20, 2012, 13:42 |
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#5 |
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Thank you for the suggestion to set the operating density to zero; it seems to work well now
Thank you for your replies |
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January 20, 2012, 14:01 |
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#6 |
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January 20, 2012, 14:04 |
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#7 |
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It is single phase; just trying to see if the "gravity" option makes a difference in the pressures in a pipe
As a next step I am contemplating to write a UDF to try and modify the gravity vector. Would someone know how to to this? |
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January 20, 2012, 14:15 |
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#8 |
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Are you talking about modifying the gravity vector as the simulation proceeds, or modification to be something other than -9.81 m/s^2 in the "down" direction? If you're looking at simply modifying it from -9.81, this is what you're specifying in the X, Y, and Z components of gravity when you turn it "on." Instead of -9.81 in the Z direction, if you make it -9.81 in the Y direction, gravity will now be "sideways" instead of "down" as in your previous case.
ComputerGuy |
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January 20, 2012, 14:19 |
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#9 |
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Gravity will be rigidly defined for the entire simulation, but want to make it vary with altitude
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