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Old   September 30, 2021, 01:54
Default Output of force
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Wenyu Zhao
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Hello, I want to output the breaking wave force on the square structure under different rotation angles. I set the terrain with the command of 'o' and the structure with the command of's', but there is no force output in 'REEF3D_CFD_Forcesolid-1.dat'file, and many' nan 'characters appear. The following is my output file and the contents of the 'control. txt' file. Can you help me see what's wrong?
'REEF3D_CFD_Forcesolid-1.dat'file
x_start xend y_start y_end z_start z_end
43.3 44.7 . 1.8 3.2 . 2.3 7


it time Fx Fy Fz
2 0.00614574722 nan nan nan
3 0.00883904188 nan nan nan
4 0.0117192588 nan nan nan
5 0.0145134942 nan nan nan
6 0.0173044542 nan nan nan
7 0.0201809681 nan nan nan
8 0.0232861434 nan nan nan
9 0.02665776 nan nan nan
10 0.0300338007 nan nan nan
11 0.0332941716 nan nan nan
12 0.0363535086 nan nan nan
13 0.0391774851 nan nan nan

'control. txt' file
C 11 6
C 12 21
C 13 21
C 14 8
C 15 21
C 16 3

B 1 0.05
B 10 0.0 54.0 0.0 5 0.0 7.0

S 10 43.65 44.35 2.15 2.85 2.3 7
S 5 44 2.5 2.3 0 0 27

O 61 21.0 44.0 0.0 5.0 0.0 2.30
O 10 44.0 54.0 0.0 5.0 0.0 2.30

M 20 2

M 10 12
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Old   September 30, 2021, 02:43
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Arun Kamath
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The O commands are now deprecated. Please use the S commands for your object.
Also in your ctrl.txt file, use the P 81 command to define a box around your structure to generate values for forces.
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Old   October 1, 2021, 07:35
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Wenyu Zhao
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Quote:
Originally Posted by kamath View Post
The O commands are now deprecated. Please use the S commands for your object.
Also in your ctrl.txt file, use the P 81 command to define a box around your structure to generate values for forces.
ok, thank you very much! The problem has been solved.
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Old   January 22, 2024, 00:14
Question REEF3D_ 6DOF_ forces X 180
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wengxinyu
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Hello, I am using the X 180 floating body ;In REEF3D_ 6DOF_ forces file, after each time step, the magnitude of the force change is too large, which is not consistent with the actual test results. When I use a scatter plot to view Fz data, the image presents three smooth curves.Can you help me solve this problem?This is my calculation file
Attached Images
File Type: jpg line.jpg (25.2 KB, 16 views)
File Type: jpg scatter.jpg (39.0 KB, 15 views)
Attached Files
File Type: txt control.txt (158 Bytes, 1 views)
File Type: txt ctrl.txt (938 Bytes, 2 views)
File Type: zip floating.zip (1.9 KB, 3 views)

Last edited by userweng; January 22, 2024 at 07:20.
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Old   January 22, 2024, 10:33
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Ahmet Soydan
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Please use the latest version of REEF3D. I also recommend using N 40 4 for floating body simulations.

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Originally Posted by userweng View Post
Hello, I am using the X 180 floating body ;In REEF3D_ 6DOF_ forces file, after each time step, the magnitude of the force change is too large, which is not consistent with the actual test results. When I use a scatter plot to view Fz data, the image presents three smooth curves.Can you help me solve this problem?This is my calculation file
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Old   January 23, 2024, 02:28
Question oscillation between Fz and Fx
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Thank you, I have updated to the latest version of REEF3D and DiveMESH, and used N 40 4 for simulation, but there is still some oscillation between Fz and Fx. Is this normal?
Attached Images
File Type: png Fz.png (189.0 KB, 18 views)
Attached Files
File Type: txt ctrl.txt (792 Bytes, 2 views)
File Type: txt control.txt (165 Bytes, 2 views)
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Old   January 23, 2024, 05:20
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I'm not sure if this result is from the case you shared but if so, the Bcs on the side walls must be a symmetry plane because this is a 2D simulation.

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Originally Posted by userweng View Post
Thank you, I have updated to the latest version of REEF3D and DiveMESH, and used N 40 4 for simulation, but there is still some oscillation between Fz and Fx. Is this normal?
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Old   January 23, 2024, 07:39
Question This doesn't work
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This doesn't work, sir. This is my calculation file,can you check it?
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File Type: zip floating example.zip (4.9 KB, 1 views)
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Old   March 7, 2024, 21:52
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Yupeng Duan
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Quote:
Originally Posted by kamath View Post
The O commands are now deprecated. Please use the S commands for your object.
Also in your ctrl.txt file, use the P 81 command to define a box around your structure to generate values for forces.
Hi
according to the user guid manuel, it seems that the user can only define a "force box" to out put the force , how can I out put the force for the side-by-side fixed boxs separately.
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