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Old   September 2, 2010, 02:58
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Henry Arrigo
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I v a problem with solving a DFBI case. I want too run a boat with thrust force in a domain. is that possible? I mean instead of setting a velocity inlet i want to move the boat using a force acting on it. this case is very helpful to study maneuvering. I v already solved a simple case, but the results are not reliable for example free surface deformation is unreasonable and drag force plot is strange too, but as i expected the whole domain moves in the direction of applied force, and also boat motions seems to be rational. do you have any idea how to come up with this case?
thank you
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Old   September 12, 2010, 19:57
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If your results are looking strange, there is an error in the set up. Is your domain wide enough? Which boundary conditions do you have? What about the mesh resolution near the surface?
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Old   September 13, 2010, 07:36
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Henry Arrigo
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A domain is created to extend 2*L aft-ward,L forward, and L side-ward from the boat. also L to the top of the domain and 2*L to the bottom. I sett B.Cs as mass flow inlet with rate value equal to zero for inlet and outlet and non-sleep wall for other four faces. and about the mesh resolution, here is the report of volume range: Volume range: [3.9930201368e-009, 9.4388723373e-002] m^3.
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Old   September 23, 2010, 15:03
Post DFBI maneuvering
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Naimish Harpal (MS Aerospace Engr)
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Hi,
First of all, I wanted to know what CFD tool do you use for your DFBI problem? BTW, I am doing the same kind of analysis using NUMECA Fine/Marine. Instead of specifying Inlet BC velocity, I specified various maneuvering style (constant, ramp, sinusoidal, ...etc) to the body centroid. For constant velocities cases, my CFD results were matching with the experimental data.
Anyways, there is a option for external forces under Motion laws, but I havn't tried this option yet. May be you can look into more details at http://www.numeca.com/index.php?id=finemarine.

Thanks.
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Old   September 23, 2010, 15:21
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Henry Arrigo
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It s obviously STAR-CCM+. Anyway, thank you for your recommendation but I m trying to do this with STAR-CCM+. I know it s feasible. Anyway, Thank you again.
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