FSI DRAGON FLY SIMULATION

[ranga1990]

I am at present dealing with the wings of a dragon fly. I am trying to set up a motion for that in ABAQUS 6.10 which rotates the wing 180 degrees. I have initially applied pressure force on the wing and made it flap but i am trying to make it rotate without using the force/pressure. I have frequency with me. The CFD tool that i am using for this FSI is CRADLE. As a result of FSI the pressure is taken in the ABAQUS from the CFD tool as input. This shows i need not apply pressure force in ABAQUS. All i want to do is set up a motion for the wing using frequency by fixing a reference point.

Can you please guide me with the procedure.

Thanks for your valuable time.

 

[rstupplebeen]

1.Create a reference point
2.Interaction>Constraint>Create>Coupling
3.Choose the reference point and 1 wing
4.Load>BC>Displacement Rotation
5.Select the reference point and apply your deformations and reference an amplitude associated with your wing motion.
6.Repeat for remaining wings
I hope this helps.

Rob Stupplebeen

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

 

[ranga1990]

I could create the reference point and also did the interaction part but how do i make it flap 0 degrees to 180 degrees? As in what kind of boundary conditions do i use for that?

Thanks
Ranga

 

[rstupplebeen]

Displacement/Rotation
U1=X
U2=Y
U3=Z
UR1=Rotation about X...
Note that the units are radians.

Rob Stupplebeen

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

 

[ranga1990]

I have got the movement of the wing but i am getting confused with he reference point. I am sending you the file along with this. can you have a look at it please,

Thanks a bunch
Ranga

 

[ranga1990]

This is my file.

 

[rstupplebeen]

Currently you have 0 displacement assigned to all but UR3 and Amp-1 called out. Depending on your required motions you will probably need to create a new constraint and amplitude for each DOF. Also I typically use 1 for the displacement and let the amplitude determine the magnitude from there. I believe all of the motion that you are seeing is because of your concentrated force also uses Amp-1.

It might be worth trying to explain exactly what you are trying to do. Specifically what inputs you have and what your desired outputs are.

I hope this helps.

Rob Stupplebeen

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

 

[ranga1990]

The wing is flapping only because i have applied pressure on it but i want the wing to flap because of the motion. As in i want to fix a reference point, make the body rigid and give it a rotation of 180 degrees.

This is what i actually want to do but not able to do it.

 

[ranga1990]

I dont have any force as input.

 

[rstupplebeen]

Check out this similar post I helped with a while back.

http://www.eng-tips.com/viewthread.cfm?qid=299958

Rob Stupplebeen

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

 

[ranga1990]

Can you please explain me the meaning of this error?

THERE IS NO ELEMENT AVAILABLE IN THE MODEL TO CONTROL THE STABLE TIME INCREMENT FOR STEP-1. PLEASE ADD DEFOEMABLE ELEMENT TO CONTROL THE STABLE TIME INCREMENT.

 

[rstupplebeen]

Explicit analyses need to cut the step time to be less than the stable time increment. It is calculated as the time it takes to get through the smallest element and is related to stiffness and density. Basically since you do not have any deformable elements it does not know what to do. Try solving in standard instead of explicit.



Rob Stupplebeen

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