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dimensional or dimensionless?

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Old   July 28, 2012, 16:29
Default dimensional or dimensionless?
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Hi Foamers

can some1 clear this for me plz:
is OpenFoam a dimensional solver? or dimensionless solver like fluent?
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Old   July 29, 2012, 08:45
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fluent is dimensionless solver?
however OpenFOAM, check dimensions, and its dimensional solver without doubt
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Old   July 29, 2012, 13:47
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Thanks Nima
i think i couldn't ask my question in a good way!

my means was that if in simulation we want the Re=(u*d)/nu=180 , Can we set velocity(u), diameter(d) or nu in arbitary values to obtain Re=180 ?

means: is simulation with u=180 m/s , d=1 m , nu=1 same with simulation with u=180*10^-6 , d=1 , nu=10^-6 ????

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Old   July 29, 2012, 14:50
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mathematically, yes. but by the view of numerical method, it maybe has differences for numerical methods used.
but I checked it for a single cylinder as a test case, I have got the same answers.
U=100, nu=1,<==>U=1,nu=0.01
but there is difficulty in convergence of answer in first test case.
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Old   July 30, 2012, 07:37
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Thanks niaz, was useful

So, i can change the values of air and water's properties in interfoam to obtain the Reynolds and Froude number that i want. and the only difficulty is convergence?
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Old   July 30, 2012, 13:27
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Quote:
Originally Posted by amin66 View Post
Thanks niaz, was useful

So, i can change the values of air and water's properties in interfoam to obtain the Reynolds and Froude number that i want. and the only difficulty is convergence?
yes, but be careful, to change all parameters correctly manner.
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Old   August 1, 2012, 08:20
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Thank you so much
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