CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > REEF3D

Output of force

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 30, 2021, 01:54
Default Output of force
  #1
New Member
 
Wenyu Zhao
Join Date: Apr 2021
Posts: 18
Rep Power: 5
Andrea-wwwwwwww is on a distinguished road
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
Andrea-wwwwwwww is offline   Reply With Quote

Old   September 30, 2021, 02:43
Default
  #2
Senior Member
 
Arun Kamath
Join Date: Nov 2014
Location: Trondheim, Norway
Posts: 265
Rep Power: 13
kamath is on a distinguished road
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.
__________________
Arun
X years with REEF3D
kamath is offline   Reply With Quote

Old   October 1, 2021, 07:35
Default
  #3
New Member
 
Wenyu Zhao
Join Date: Apr 2021
Posts: 18
Rep Power: 5
Andrea-wwwwwwww is on a distinguished road
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.
Andrea-wwwwwwww is offline   Reply With Quote

Old   January 22, 2024, 00:14
Question REEF3D_ 6DOF_ forces X 180
  #4
New Member
 
wengxinyu
Join Date: Jun 2022
Posts: 3
Rep Power: 4
userweng is on a distinguished road
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, 23 views)
File Type: jpg scatter.jpg (39.0 KB, 19 views)
Attached Files
File Type: txt control.txt (158 Bytes, 3 views)
File Type: txt ctrl.txt (938 Bytes, 6 views)
File Type: zip floating.zip (1.9 KB, 8 views)

Last edited by userweng; January 22, 2024 at 07:20.
userweng is offline   Reply With Quote

Old   January 22, 2024, 10:33
Default
  #5
New Member
 
Ahmet Soydan
Join Date: Jun 2015
Location: Trondheim, Norway
Posts: 25
Rep Power: 12
soydana is on a distinguished road
Please use the latest version of REEF3D. I also recommend using N 40 4 for floating body simulations.

Quote:
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
__________________
Ahmet Soydan
Team REEF3D
www.reef3d.com
soydana is offline   Reply With Quote

Old   January 23, 2024, 02:28
Question oscillation between Fz and Fx
  #6
New Member
 
wengxinyu
Join Date: Jun 2022
Posts: 3
Rep Power: 4
userweng is on a distinguished road
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, 29 views)
Attached Files
File Type: txt ctrl.txt (792 Bytes, 5 views)
File Type: txt control.txt (165 Bytes, 4 views)
userweng is offline   Reply With Quote

Old   January 23, 2024, 05:20
Default
  #7
New Member
 
Ahmet Soydan
Join Date: Jun 2015
Location: Trondheim, Norway
Posts: 25
Rep Power: 12
soydana is on a distinguished road
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.

Quote:
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?
__________________
Ahmet Soydan
Team REEF3D
www.reef3d.com
soydana is offline   Reply With Quote

Old   January 23, 2024, 07:39
Question This doesn't work
  #8
New Member
 
wengxinyu
Join Date: Jun 2022
Posts: 3
Rep Power: 4
userweng is on a distinguished road
This doesn't work, sir. This is my calculation file,can you check it?
Attached Files
File Type: zip floating example.zip (4.9 KB, 5 views)
userweng is offline   Reply With Quote

Old   March 7, 2024, 21:52
Default
  #9
New Member
 
Yupeng Duan
Join Date: Aug 2022
Posts: 13
Rep Power: 4
YupengDuan is on a distinguished road
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.
YupengDuan is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hydrodynamic force? arun7328 STAR-CCM+ 24 July 25, 2020 04:04
Drag Force Ratio for Flat Plate Rob Wilk Main CFD Forum 40 May 10, 2020 04:47
What variable should I output to get wall force? Pauli CFX 6 May 15, 2018 07:58
writing execFlowFunctionObjects immortality OpenFOAM Post-Processing 30 September 15, 2013 06:16
RNG diverged during the analysis the flow over a multi element airfoil, why? s.m OpenFOAM Running, Solving & CFD 0 August 5, 2013 08:39


All times are GMT -4. The time now is 05:34.