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URGENT!!ERROR
Posted 08.01.2013, 09:50 GMT-5 MEMS & Nanotechnology, Fluid & Heat, MEMS & Piezoelectric Devices, Studies & Solvers 3 Replies
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Hi!during the simulation an error appears:
Failed to find a solution:
In segregated group 1: The relative error (0) is greater than the relative tolerance.
Returned solution has not converged.
What means??why it appears??what can I do?
I have a tube with two obstacles fixed with a hinge. I have to analyze the interaction between fluid and the two obstacles.
Please answer me!!!!!!
Thanks!
Failed to find a solution:
In segregated group 1: The relative error (0) is greater than the relative tolerance.
Returned solution has not converged.
What means??why it appears??what can I do?
I have a tube with two obstacles fixed with a hinge. I have to analyze the interaction between fluid and the two obstacles.
Please answer me!!!!!!
Thanks!
3 Replies Last Post 09.01.2013, 15:46 GMT-5
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Posted:
1 decade ago
Hi
sorry I cannot give you many clues, as that can come from too coarse mesh, imperfect boundary mesh, or initial conditions too far away from the final solution. FSI is tricky and require often some test and tries ...
--
Good luck
Ivar
sorry I cannot give you many clues, as that can come from too coarse mesh, imperfect boundary mesh, or initial conditions too far away from the final solution. FSI is tricky and require often some test and tries ...
--
Good luck
Ivar
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
sorry I cannot give you many clues, as that can come from too coarse mesh, imperfect boundary mesh, or initial conditions too far away from the final solution. FSI is tricky and require often some test and tries ...
--
Good luck
Ivar
These are what i've imposed:
incompressible navier stockes
subdomain settings:1=fluid domain, init=>p2(to)=100mmHg
2,3=solid domain
boundary settings:1=inlet, velocity, U=0.26m/s;
12=outlet, no viscous stress Po=0;
other=wall,no sleep
plane strain
subdomain setting:1=fluid domain
2,3=solid domain
boundary settings:4-11=fluid load
point setting:7,8=constrained
moving mesh
subdomain setting:1=fluid domain
2,3=solid domain
boundary settings:1,2,3,12=fixed
other=structural displacement
I solve with stationary segregated.
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Posted:
1 decade ago
Hi
Perhaps you need to add a small initial flow velocity or a Poiseuille pressure drop ...
One way is to solve the case in stationary (sometimes, if you have enough RAM) a direct solver converges better another possible test, but not always ;) and then to use this stationary result as initial conditions for the time series one, or a parametric sweep to ram up a flow velocity ...
certainly with the progress in solvers and solver settings a more recent version would make life easier, but that might imply new purchases for you
--
Good luck
Ivar
Perhaps you need to add a small initial flow velocity or a Poiseuille pressure drop ...
One way is to solve the case in stationary (sometimes, if you have enough RAM) a direct solver converges better another possible test, but not always ;) and then to use this stationary result as initial conditions for the time series one, or a parametric sweep to ram up a flow velocity ...
certainly with the progress in solvers and solver settings a more recent version would make life easier, but that might imply new purchases for you
--
Good luck
Ivar