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I have used SU2 for DLR F6. but it seems that the ajoint result is weird??

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Old   April 1, 2015, 12:10
Exclamation I have used SU2 for DLR F6. but it seems that the ajoint result is weird??
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chenbojian
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My F6 mesh is generated by using the nasa drag predict geometry.The Reynolds length is 0.1412. Reference aera is 0.0727.The CFD result is match with the experiment data. But the ajoint result is weird and then SU2_DOT calculate all gradients ZERO.
This is my ajoint result of drag. The Surface_Sensitivity seems not right?
And my config file.
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File Type: txt f6.txt (14.6 KB, 14 views)
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Old   April 2, 2015, 11:18
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Quote:
Originally Posted by chenbojian View Post
My F6 mesh is generated by using the nasa drag predict geometry.The Reynolds length is 0.1412. Reference aera is 0.0727.The CFD result is match with the experiment data. But the ajoint result is weird and then SU2_DOT calculate all gradients ZERO.
This is my ajoint result of drag. The Surface_Sensitivity seems not right?
And my config file.
Could you post the output history ?
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Old   April 2, 2015, 14:46
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Quote:
Originally Posted by chenbojian View Post
My F6 mesh is generated by using the nasa drag predict geometry.The Reynolds length is 0.1412. Reference aera is 0.0727.The CFD result is match with the experiment data. But the ajoint result is weird and then SU2_DOT calculate all gradients ZERO.
This is my ajoint result of drag. The Surface_Sensitivity seems not right?
And my config file.
I suggest double checking the design variable definition and smoothing options.
Design variables: they should cause a deformation to the surface specified in Marker_Designing
Smoothing: start with no smoothing
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Old   April 2, 2015, 22:16
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Originally Posted by Tommy Chen View Post
Could you post the output history ?
Sorry,my old history is overwritted. But I find it is not converge. And I calculate again, it is converging very slow. I don't have any experience about calculate the surface sensitivity. What is the right surface sensitivity range? I think the range I posted is not right.
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Old   April 2, 2015, 22:23
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Originally Posted by hlk View Post
I suggest double checking the design variable definition and smoothing options.
Design variables: they should cause a deformation to the surface specified in Marker_Designing
Smoothing: start with no smoothing
I think my Design variables are right. And also the FFD infomation. I tried to give a specified DV_VALUE to view the deform. It deformed successfully. So I doubt my Adjoint result is wrong. What dose the surface sensitivity should be? I have viewed the M6 result in TestCase. Its surface sensitivity range is (-50,50). Will this value change very large in deferent case??
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Old   April 2, 2015, 22:33
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Originally Posted by chenbojian View Post
Sorry,my old history is overwritted. But I find it is not converge. And I calculate again, it is converging very slow. I don't have any experience about calculate the surface sensitivity. What is the right surface sensitivity range? I think the range I posted is not right.
If the mean flow has not converged, you probably won't expect the adjoint to either converging or accurate.
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Old   April 2, 2015, 22:51
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Originally Posted by Tommy Chen View Post
If the mean flow has not converged, you probably won't expect the adjoint to either converging or accurate.
The mean flow is converged. I have compared it to the experiment data. I mean the adjoint result is not converged.
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Old   April 10, 2015, 23:18
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The reason is just because the DV_DEFINITION setting is not right in my config file. The FFDtag is WING_BOX but my set is 0.
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