how i can mondel a rope?

[aginor]

i want to fix a rope on two walls. then i want to put one handle one odject on this rope and mesure the sag and the sureface presure on the odject.

 

[cbrn]

Hi,
you don't suposedly need Ansys to do that.

Regards

 

[cbrn]

... I meant: please provide a bit more info on what are your goals and why you think you need a FEM for the problem. In fact, at a first glance, it's nothing you couldn't do with analytical formulas...

Regards

 

[pja]

If in fact it is something that needs to be done with FEM, the link180 element for example can be used to model rope.

 

[aginor]

i want the sag to be less than a value. so i must add some pretention. The mass is handled by a pipe. I have to edit the shape of the pipe to deform with the same way that rope deforms. In this case the surface pressure is the same in the whole pipe.

 

[cbrn]

Formulas for rope in tension will apply. The sag f = f(s) is an analytical curve called "catenary". There do exist formulas for catenaries "broken" locally by the presence of a load. The bending of the pipe is described by the classical formulas of beam-under-load. You would have to apply three ranges of equations "in series", with appropriate mutual boundary conditions.
Nothing you can't do analytically.
Of course, it MAY be faster with FEM, BUT... you have to have a software with an appropriate element formulation (tension-only link). Don't even try to model the rope in 3D with solid FE elements...