Problem of large displacements on a totally constrained SW model

Simulation Generality
1

Hi all.

So here is my problem concerning a static simulation on SolidWorks. This is a protected model, so I can't show you that clearly.

In short, it is a valve that has a certain degree of opening and I would like to determine the forces when it falls, after it has been opened. I would have liked to do a fall simulation but I have no basis in this simulation and I wondered if I would succeed in determining the faces that stop the valve etc.

To start, I made my "final" assembly with various assemblies that each represent a kinematic subassembly. Once the assembly is totally constrained, I decide to move on to a static study, with the constrained valve in the closed position.

I've had several things that have led me to several different problems that I've managed to solve, but the only one I can't seem to solve is about a big shift in my model (when everything is constrained, my whole system is bolted on, and even fixed to the wall, which I had considered as a wall, by anchoring bolts, there are pins between the floating connecting rods of my model etc) 

the application of my force is 300N at the end of a few connecting rods which are supposed to deplete the force on the valve.

During the simulation, everything works until the moment the solver starts to perform the task: "equilibrium iteration", then it stops and by clicking on ok, a message appears "Analysis of large displacements stopped
before the recording of the results" despite the fact that in the simulation otpions, the box for long displacements is natively checked.

 

sometimes in other cases, (I change small parameters) he writes to me that "the contact conditions are not respected" that the assembly is not stable, another time that the equilibrium is not reached, another time "incremental elastic deformation is too great" in short always a word to say.

 

The only doubt I have is that I must have an axle passing through 2 profiles, and a connecting rod is fixed in the middle of the axis. I don't know if you should create an axis as a part and put it in the assembly, or if you should insert an axis via the simulation (which I did for the rods, and the valve axis which have an axis that holds on 2 surfaces much closer together)

 

Can you help me?

 

Thank you very much

Regards (PJ screen carpture of the latest error and forced contacts etc)


simulation_sw.jpg
2

Solver message stopped 


simulation_sw_solveur.jpg
3

Last known error message

 

Thank you in advance.


simulation_sw_solveur_dernier_message.jpg
4

I understand your name, you have to be motivated to read everything (yes I skipped half :p )  

Try in this case, you must have a choice in the solvers, try in others, and simplify the number of parts so that it is more digestible for your PC.

---------------------------------------------------------------------------Edit: Check as a whole that the constraints don't create hyperstatism that could prevent Solid from working well.

Moreover you say with make a subset and then to have it included. Why don't you try to make the simulation. in your subset first??

Cdt 

G.

2 Likes
5

Sorry for the delay, I hadn't received a reply notification on my email.

Indeed it is long. yes he advised me to change solver (natively iterative, I went to the settings to set automatic)

I tried with my PC, and that of an employee of the company who has 16GB of RAM etc and the problem persists...

SW announces hyperstatism, and in this case why would he talk about great displacements? but I'll try to see, even if he tells me the model as "totally constrained"

I made several sub-assemblies (which are each the kinematic sub-assemblies). I'm going to try to do the simulation by sets to see if the problem persists, but the system being complex, I have to go through a simulation of the total system

 

Thank you for your answer!

6

The recessed wall does not remove all degrees of freedom. it was necessary to fix the body by a fixed geometry

 

Thank you