Problem restarting a simulation from an intermediate point.

sergiorbrett · March 14, 2010, 17:22

Hi,

I am working with a wind turbine, I am studying the transient behavior of the rotor from 0 rpm to stationary condition. I am using Fortran subroutines in ANSYS 11, I tried with ANSYS 12, but It has problems to work with subroutines.

I created the subroutine, the mesh, and I validated the result in an stationary conditions. Now I am running the transient simulation, but although I am getting convergency within about 4 loops for each time step, after 308 iterations, the convergency can't be reach. I have some modifications to my .def, but I can't to restart the simulations from the last iteration converged.

I couldn't find a tutorial for this function, and in the help the information is very un usefull for me.

Could anybody explain to me how to restart the simulation from a intermediate point of a previos simulation.

Thanks

JDA · April 21, 2010, 16:16

In the solver manager Define Run window check initial values specification and browse to the .res, .bak (backup), or .trn (transient) file you want to retrieve results from as initial conditions. If you have a steady state simulation and did not write any backup files, I'm not aware of a way to retrieve initial conditions for some intermediate step. This function also will interpolate initial values onto a mesh of a different size than the original mesh.

I hope this answers your question. If not, write back and I'll take another stab or maybe someone else will have a better idea.

sergiorbrett · April 21, 2010, 17:11

Hi,

I have a transient simulation, and I am saving the results every 2 timesteps. I think that the problem is that I am not saving all the variables but just a few which are really important. Do you think that the problem could be this, do I need the complete variables for every timesteps.

Thanks for answering

March 14, 2010, 17:22	Problem restarting a simulation from an intermediate point.	#1
sergiorbrett New Member Sergio Brett Join Date: Jul 2009 Posts: 14 Rep Power: 16	Hi, I am working with a wind turbine, I am studying the transient behavior of the rotor from 0 rpm to stationary condition. I am using Fortran subroutines in ANSYS 11, I tried with ANSYS 12, but It has problems to work with subroutines. I created the subroutine, the mesh, and I validated the result in an stationary conditions. Now I am running the transient simulation, but although I am getting convergency within about 4 loops for each time step, after 308 iterations, the convergency can't be reach. I have some modifications to my .def, but I can't to restart the simulations from the last iteration converged. I couldn't find a tutorial for this function, and in the help the information is very un usefull for me. Could anybody explain to me how to restart the simulation from a intermediate point of a previos simulation. Thanks

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April 21, 2010, 16:16		#2
JDA New Member J. D. Aurand Join Date: Apr 2010 Posts: 13 Rep Power: 16	In the solver manager Define Run window check initial values specification and browse to the .res, .bak (backup), or .trn (transient) file you want to retrieve results from as initial conditions. If you have a steady state simulation and did not write any backup files, I'm not aware of a way to retrieve initial conditions for some intermediate step. This function also will interpolate initial values onto a mesh of a different size than the original mesh. I hope this answers your question. If not, write back and I'll take another stab or maybe someone else will have a better idea.

April 21, 2010, 17:11		#3
sergiorbrett New Member Sergio Brett Join Date: Jul 2009 Posts: 14 Rep Power: 16	Hi, I have a transient simulation, and I am saving the results every 2 timesteps. I think that the problem is that I am not saving all the variables but just a few which are really important. Do you think that the problem could be this, do I need the complete variables for every timesteps. Thanks for answering