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December 28, 2009, 07:49 |
about Rayleigh numbe
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#1 |
New Member
Nabil
Join Date: Dec 2009
Posts: 7
Rep Power: 16 |
hi all
how can i get or calculate Rayleigh number. related docs: http://en.wikipedia.org/wiki/Rayleigh_number best regards |
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December 28, 2009, 15:07 |
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#2 | |
Senior Member
Sebastian Gatzka
Join Date: Mar 2009
Location: Frankfurt, Germany
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Rep Power: 20 |
Quote:
Or try to give us some more details.
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December 29, 2009, 09:39 |
about Rayleigh number
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#3 |
New Member
Nabil
Join Date: Dec 2009
Posts: 7
Rep Power: 16 |
hi sega
i want an utility tool, or some help to develop once to calculate Rayleigh number as field. to do this i need - rho field - T field - nu and alpha |
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December 31, 2009, 04:09 |
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#4 |
Senior Member
Sebastian Gatzka
Join Date: Mar 2009
Location: Frankfurt, Germany
Posts: 729
Rep Power: 20 |
Do you have any knowledge about OpenFOAM programming so far, or are you a beginner?
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December 31, 2009, 08:08 |
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#5 |
New Member
Nabil
Join Date: Dec 2009
Posts: 7
Rep Power: 16 |
i am new in openfoam programming, do you think that openfoam programming guide is enough to write a small utility.
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December 31, 2009, 08:45 |
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#6 | |
Senior Member
Sebastian Gatzka
Join Date: Mar 2009
Location: Frankfurt, Germany
Posts: 729
Rep Power: 20 |
Quote:
I suggest you take a look at the slides from the 4th OpenFOAM Workshop. Especially the Basic Training slides should be of interest to you. In particular these: Have fun!
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January 4, 2010, 05:34 |
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#7 |
New Member
Nabil
Join Date: Dec 2009
Posts: 7
Rep Power: 16 |
thank you sega for your help and time
after reading this material i know how -compile an solver -add a new scalartransportproprieties like nu -declaration of fields in creatfields.H i hope to implement my own solver but there is some thing i dont understand when i tray to compile this equation inspired from programming tutorial d(T)/dt + U*grad(T) = nu*laplacian(T) i get some thing like this [caelinux@localhost icoFoam]$ wmake Making dependency list for source file icoFoam.C SOURCE=icoFoam.C ; g++ -m32 -Dlinux -DDP -Wall -Wno-strict-aliasing -Wextra -Wno-unused-parameter -Wold-style-cast -O3 -DNoRepository -ftemplate-depth-40 -I/home/caelinux/OpenFOAM/OpenFOAM-1.4.1/src/finiteVolume/lnInclude -IlnInclude -I. -I/home/caelinux/OpenFOAM/OpenFOAM-1.4.1/src/OpenFOAM/lnInclude -fPIC -pthread -c $SOURCE -o Make/linuxGccDPOpt/icoFoam.o icoFoam.C: In function ‘int main(int, char**)’: icoFoam.C:83: error: no match for ‘operator==’ in ‘Foam::fvm::laplacian(const Foam::volScalarField&, Foam::GeometricField<Type, Foam::fvPatchField, Foam::volMesh>&) [with Type = double](((Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>&)(& p))) == Foam:perator-(const Foam::tmp<Foam::GeometricField<Type, PatchField, GeoMesh> >&) [with Type = Foam::Vector<double>, PatchField = Foam::fvPatchField, GeoMesh = Foam::volMesh]()’ /home/caelinux/OpenFOAM/OpenFOAM-1.4.1/src/OpenFOAM/lnInclude/cellModelI.H:124: note: candidates are: bool Foam:perator==(const Foam::cellModel&, const Foam::cellModel&) /home/caelinux/OpenFOAM/OpenFOAM-1.4.1/src/OpenFOAM/lnInclude/edgeI.H:147: note: bool Foam:perator==(const Foam::edge&, const Foam::edge&) make: *** [Make/linuxGccDPOpt/icoFoam.o] Error 1 what that mean, if you know, errors related to operator== operator+ |
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January 4, 2010, 05:38 |
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#8 |
Senior Member
Sebastian Gatzka
Join Date: Mar 2009
Location: Frankfurt, Germany
Posts: 729
Rep Power: 20 |
Well how did you actually implement the equation?
Can you show us some code? How is this related to the Rayleigh number?
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Schrödingers wife: "What did you do to the cat? It's half dead!" |
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January 4, 2010, 06:08 |
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#9 |
New Member
Nabil
Join Date: Dec 2009
Posts: 7
Rep Power: 16 |
the goal is to do some simulation for a specified Ra number 10E4 .. 10E7
Ra number is used in dimensionless "no dimonsioned" equations like here http://www-cast3m.cea.fr/cast3m/html...35/node50.html Ra=Gr.Pr but open foam use a dimensioned equations so i have two choice use openfoam dimensioned equations and calculate Ra number after or write a new solver " equation with no dimension by changing dimension parameters in SetDimension.H", i prefer this second coice because i can control Ra numbre and i dont have to calculate it i guess what do you think ragards |
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