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High Y plus wall values despite sizing, inflation and refinement

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Old   July 23, 2012, 12:48
Default High Y plus wall values despite sizing, inflation and refinement
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i am getting high wall y plus values despite sizing, inflation and refinement. i am gtg value in exp of 5 or 4 desired values are for SA model. help required.
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Old   July 23, 2012, 14:50
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Could you rephrase the question? I didn't get it.
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Old   July 23, 2012, 14:53
Default elaboration of the query
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sir i am interested to model flow around an aircraft at mach 0.8. i am using SA model and facing problem of high y plus value they are in range of 3 exp 5. i have refined my mesh and changed settings for my inflation layers. however yet the values are not coming down. need guidance on this issue.
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Old   July 24, 2012, 03:07
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What's the thickness of the first cell at the wing? What's the size of the aircraft?
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Old   July 24, 2012, 03:19
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Did I get you correctly? Althoug you change the thickness of the first cell, the Yplus values do not change?
I can't recall such a bug in Fluent.
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Old   July 24, 2012, 06:27
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the size of aircraft is around 18 m long and the thickness of first layer is 1 exp -7. still the Y plus is very high. may be i am doing some things wrong. the mesh quality as per skewness and orthogonal quality is good.
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Old   July 24, 2012, 06:30
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So your first layer thickness is 100nm? Did your solution converge? What's the largest residual?
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Old   July 30, 2012, 15:09
Default Convergence values
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sir the convergence values are 1 exp -3. i have also used mesh adaptation but no avail. i seek guidance on this regard.
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Old   July 31, 2012, 15:20
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Originally Posted by nauman55 View Post
sir the convergence values are 1 exp -3. i have also used mesh adaptation but no avail. i seek guidance on this regard.
thanx
I guess you have not scaled your mesh in fluent, check upon this. BTW you are using structured hexa mesh or tetra mesh for your problem?
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Old   July 31, 2012, 15:44
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sir mesh is scaled in the same units. i have tried both hexa and tetra meshes to get desired values but no avail.
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Old   August 1, 2012, 04:06
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could you please share your geometry and mesh file with me along with flow and boundary conditions if its not confidential, I will try on it and will let you know.... are you making your mesh in ICEM or Gambit or anyother software?
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Old   August 1, 2012, 04:47
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sure sir if i may have ur email address. my email is naumaneshanhashmi@gmail.com if you can send me a blank email, i will send you the requisite files.
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Old   August 1, 2012, 11:54
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sure sir if i may have ur email address. my email is naumaneshanhashmi@gmail.com if you can send me a blank email, i will send you the requisite files.
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my email id is yasirforfriends@yahoo.com
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Old   August 1, 2012, 16:14
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kindly mail me the parasolid or acis(sat) version of your geometry as I use ICEM for meshing. Thanks

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