CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   FLOW-3D (https://www.cfd-online.com/Forums/flow-3d/)
-   -   Linking two floating objects (https://www.cfd-online.com/Forums/flow-3d/94841-linking-two-floating-objects.html)

chatluthier November 28, 2011 06:09

Linking two floating objects
 
Hello,

Could someone tell me how to constrain two floating objects, when a rope or spring is not suitable? I want to modelize a constrained motion in X and Y translations (the two objects move together), but free in rotation (at least aroud Y) and in Z translation.
At least one of the two object should have a coupled motion (i.e. floating)

Thany you for your help!

MuxaB December 12, 2011 01:44

What do the two objects represent?

chatluthier December 12, 2011 04:55

Re
 
Hello,

there is a pushing boat and a barge. In the actual world, they are connected by claws on the pushing boat side hung on cylinders on the barge side so that they can translate in the Z direction.
For the moment, I decided to precribe the same speed for the two floating objects in X, and let them adjust in Z height and Y rotation.
To accurately simulate the link, I think the simplest would be to insert control forces on the pushing boat (Xdrag of pusher + barge on the helixes location, and Xdrag of the barge only on the claws location). My problem here is to have Flow tell me the drag value... if you know how to do it...:confused:

If you have any better idea, I would be glad to hear it :)

MuxaB December 12, 2011 12:31

Quote:

Originally Posted by chatluthier (Post 335498)
Hello,

there is a pushing boat and a barge. In the actual world, they are connected by claws on the pushing boat side hung on cylinders on the barge side so that they can translate in the Z direction.
For the moment, I decided to precribe the same speed for the two floating objects in X, and let them adjust in Z height and Y rotation.
To accurately simulate the link, I think the simplest would be to insert control forces on the pushing boat (Xdrag of pusher + barge on the helixes location, and Xdrag of the barge only on the claws location). My problem here is to have Flow tell me the drag value... if you know how to do it...:confused:

If you have any better idea, I would be glad to hear it :)

What is you use small stiff springs to attach the two objects to each other? Three should be enough, but can be more to achieve proper coupling.


All times are GMT -4. The time now is 16:33.