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Difference between MRF and RBM

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Old   January 11, 2012, 06:06
Post Difference between MRF and RBM
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Hi Everyone, I am new to Star CCM+, What is the difference between moving reference frame and rigid body motion. Except the difference like moving mesh in RBM(unsteady), stationary in MRF(steady).May i know what are all the other difference.
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Old   January 12, 2012, 17:16
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I will give this a try.
In MRF the different bodies are fixed in position but the fluid feels the forces as if the bodies were moving. This will often be good enough for axisymmetric geometry.
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Old   January 12, 2012, 17:56
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in rigid body motion the reference system stays still, and the domain/flow/mesh is moving.

in mrf, as the name suggest, the entire system is moving. because this method is less computationally expensive than the rbm, it is successfully used in, for example, rotating parts, turbiles, isolated propeller analysis (in case of a rotation)
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Old   August 12, 2012, 23:45
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Quote:
Originally Posted by sail View Post
in rigid body motion the reference system stays still, and the domain/flow/mesh is moving.

in mrf, as the name suggest, the entire system is moving. because this method is less computationally expensive than the rbm, it is successfully used in, for example, rotating parts, turbiles, isolated propeller analysis (in case of a rotation)
hi ...
do u know how to use reference frame in turbine analysis
need to know ,the turbine RPM given the mas flow rate as input

thanx
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Old   August 21, 2012, 23:39
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Quote:
Originally Posted by saleh alsubari View Post
hi ...
do u know how to use reference frame in turbine analysis
need to know ,the turbine RPM given the mas flow rate as input

thanx
sorry to disappoint you, but I belive that to get the rpm you'll need to use the RBM tecnique
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Old   August 21, 2012, 23:45
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Originally Posted by sail View Post
sorry to disappoint you, but I belive that to get the rpm you'll need to use the RBM tecnique
thanx for replying ...
can u plz elaborate ,about RBM techinqes cuz i have not used that one so far...
thanx a gain
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Old   August 28, 2012, 20:49
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Originally Posted by sail View Post
sorry to disappoint you, but I belive that to get the rpm you'll need to use the RBM tecnique
I'm sorry I have to disagree. It's just a matter of accuracy and computing time whether to use RBM or MRF. You'll get a (less acurate) result using MRF, but it might still be better than a bad RBM result.
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