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Flapping Wing motion

Flapping Wing motion

Flapping Wing motion

(OP)
Hello All,

I want to implement a flapping wing motion in Abaqus.
The wing flaps about a fixed point in the global axis and rotates about
its own axis.
I also have simple sinusoidal functions to describe the motions.

Kindly assist me to implement this in Abaqus.

Please have a look at a sample animation done in Fluent to give you a
clear idea, from the web site below.

http://www.2shared.com/photo/W5aWtYOK/WingMotion-5.html


Thank you in advance.


 

RE: Flapping Wing motion

Create 2 reference points and tie the respective wing edges.  Apply boundary conditions to the reference points with amplitudes corresponding to your sinusoidal functions.  I hope this helps.

What are you trying to simulate a dragonfly?  Any plans on FSI?

Rob Stupplebeen
https://sites.google.com/site/robertkstupplebeen/

RE: Flapping Wing motion

(OP)
Thanks for the information.

I will try your suggestion.

Hope it works.

And yes I am planning to FSI.

Cheers

RE: Flapping Wing motion

(OP)
Dear Rob,

I tried using reference point approach. But the wing model does not move at all. I am not sure where I am going wrong.

I hope I dont sound clingy if I request you help me implement just one wing with one sinusoidal motion.

It is only my first week in Abaqus, and I have not guidance what so ever.

Many thanks in advance,

Best Regards,
  

RE: Flapping Wing motion

Please see attached video and INP below.  I hope this helps.


*Heading
** Job name: Wing Model name: Model-1
** Generated by: Abaqus/CAE 6.10-EF1
*Preprint, echo=NO, model=NO, history=NO, contact=NO
**
** PARTS
**
*Part, name=Wing
*Node
      1,           0.,           0.,           0.
      2,          0.5,           0.,           0.
      3,           1.,           0.,           0.
      4,           0.,          0.5,           0.
      5,          0.5,          0.5,           0.
      6,           1.,          0.5,           0.
      7,           0.,           1.,           0.
      8,          0.5,           1.,           0.
      9,           1.,           1.,           0.
     10,           0.,          1.5,           0.
     11,          0.5,          1.5,           0.
     12,           1.,          1.5,           0.
     13,           0.,           2.,           0.
     14,          0.5,           2.,           0.
     15,           1.,           2.,           0.
     16,           0.,          2.5,           0.
     17,          0.5,          2.5,           0.
     18,           1.,          2.5,           0.
     19,           0.,           3.,           0.
     20,          0.5,           3.,           0.
     21,           1.,           3.,           0.
     22,           0.,          3.5,           0.
     23,          0.5,          3.5,           0.
     24,           1.,          3.5,           0.
     25,           0.,           4.,           0.
     26,          0.5,           4.,           0.
     27,           1.,           4.,           0.
     28,           0.,          4.5,           0.
     29,          0.5,          4.5,           0.
     30,           1.,          4.5,           0.
     31,           0.,           5.,           0.
     32,          0.5,           5.,           0.
     33,           1.,           5.,           0.
*Element, type=S4R
 1,  1,  2,  5,  4
 2,  2,  3,  6,  5
 3,  4,  5,  8,  7
 4,  5,  6,  9,  8
 5,  7,  8, 11, 10
 6,  8,  9, 12, 11
 7, 10, 11, 14, 13
 8, 11, 12, 15, 14
 9, 13, 14, 17, 16
10, 14, 15, 18, 17
11, 16, 17, 20, 19
12, 17, 18, 21, 20
13, 19, 20, 23, 22
14, 20, 21, 24, 23
15, 22, 23, 26, 25
16, 23, 24, 27, 26
17, 25, 26, 29, 28
18, 26, 27, 30, 29
19, 28, 29, 32, 31
20, 29, 30, 33, 32
*Nset, nset=_PickedSet3, internal, generate
  1,  33,   1
*Elset, elset=_PickedSet3, internal, generate
  1,  20,   1
** Section: PP
*Shell Section, elset=_PickedSet3, material=PP
0.1, 5
*End Part
**  
**
** ASSEMBLY
**
*Assembly, name=Assembly
**  
*Instance, name=Wing-1, part=Wing
*End Instance
**  
*Node
      1,           0.,           0.,           0.
*Nset, nset=_PickedSet11, internal
 1,
*Nset, nset=_PickedSet12, internal
 1,
*Elset, elset=__PickedSurf10_E1, internal, instance=Wing-1
 1, 2
*Surface, type=ELEMENT, name=_PickedSurf10, internal
__PickedSurf10_E1, E1
** Constraint: Constraint-1
*Coupling, constraint name=Constraint-1, ref node=_PickedSet11, surface=_PickedSurf10
*Kinematic
*End Assembly
*Amplitude, name=Amp-2
          0.,           0.,         0.25,           1.,          0.5,           0.,         0.75,           1.
          1.,           0.
**
** MATERIALS
**
** http://www.matweb.com/search/DataSheet.aspx?MatGUID=08fb0f47ef7e454fbf7092517
** b2264b2
**
** fric 0.250
*Material, name=PP
*Density
 9.34e-11,
*Elastic
1800., 0.425
**
** BOUNDARY CONDITIONS
**
** Name: BC-1 Type: Displacement/Rotation
*Boundary
_PickedSet12, 1, 1
_PickedSet12, 2, 2
_PickedSet12, 3, 3
_PickedSet12, 4, 4
_PickedSet12, 5, 5
_PickedSet12, 6, 6
** ----------------------------------------------------------------
**
** STEP: Step-1
**
*Step, name=Step-1, nlgeom=YES, inc=10000
*Static
0.1, 1., 1e-08, 0.1
**
** BOUNDARY CONDITIONS
**
** Name: BC-1 Type: Displacement/Rotation
*Boundary, amplitude=Amp-2
_PickedSet12, 1, 1
_PickedSet12, 2, 2
_PickedSet12, 3, 3
_PickedSet12, 4, 4, 1.
_PickedSet12, 5, 5
_PickedSet12, 6, 6
**
** OUTPUT REQUESTS
**
*Restart, write, frequency=0
**
** FIELD OUTPUT: F-Output-1
**
*Output, field, variable=PRESELECT
**
** HISTORY OUTPUT: H-Output-1
**
*Output, history, variable=PRESELECT
*End Step

 

Rob Stupplebeen
https://sites.google.com/site/robertkstupplebeen/

RE: Flapping Wing motion

(OP)
Great !

Thank you very much for your help.

I will implement it as per your input file.

Thanks a lot again.

Kind Regards,
 

RE: Flapping Wing motion

(OP)
Dear Rob,

Thanks for your previous input. Based on your model I have made a solid model and was successfully able to implement the single flapping motion using amplitude input from a tabular data.

However I am facing a little bit of problem in getting the rotation about the wing axis.
Since wing axis is also moving as the wing flaps, for the rotation about wing axis, I have resolved this rotation about X and Z-axis. But it doesnt seem to be working properly.

I strongly feel I am missing one small detail and I am hoping to get your help.

I am sending you the file and 2 videos showing, flapping without rotation and flapping with rotation, for your reference.

http://www.mediafire.com/file/iw8vml5ui6es94x/Flapping-Rob.zip
http://www.mediafire.com/file/oxxua0a3v6ui6bb/Flap-Without-Rotation.avi
http://www.mediafire.com/file/9hh0q4sq2003qxd/Flap-With-Rotation.avi


I deeply appreciate your help in this .

Thank you
Best Regards,
Vishal
 

  

RE: Flapping Wing motion

Vishal,

I looked at your model and I think that the error is because you are defining rotational velocities.  Did you intend on specifying rotational velocity or rotation angle?  I hope this helps.

Rob Stupplebeen
https://sites.google.com/site/robertkstupplebeen/

RE: Flapping Wing motion

(OP)
Yes Rob,

I intend to define rotational velocities because they are cummutative, unlike rotational angles. May be I am not following the coventional correctly , I am not sure.

Thanks
 

RE: Flapping Wing motion

(OP)
I believe angular displacement would work if there is a way I can define a local coordinate system which has a Y-axis(flapping axis) in line with the global Y-axis. And each time step the wing flaps, this local coordinate system rotates as well, and I can define the rotation of the wing about the local X-axis.

Thanks for your help again.
 

RE: Flapping Wing motion

(OP)
Hi Rob !

I finally implemented the correct motion.
The solution was to turn on the Non-linear option.

Thanks a lot for your timely help.
Cheers.

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