Multi-Step Analysis
Multi-Step Analysis
(OP)
Dear Colleague,
I have a silly question. I would like to do multi-step analysis for a monopile of offshore wind turbine . The first step is static analysis where I need to obtain the stresses and displacements. Next I want to couple the buckling analysis to the first step. I have define the second step however when I run the simulation I get the following error message:
DIFFERENTIAL STIFFNESS MATRIX IS COMPLETELY NULL. THE EIGENPROBLEM CANNOT BE SOLVED. IN A *BUCKLE ANALYSIS THE MOST LIKELY CAUSE IS THAT A NONZERO LOADING PATTERN WAS NOT SPECIFIED VIA *BOUNDARY, *CLOAD, *DLOAD, ETC
I have tried to use the restart attributes but I could not make it work.
Any help would be greatly appreciated.
Regards,
Ariyan
I have a silly question. I would like to do multi-step analysis for a monopile of offshore wind turbine . The first step is static analysis where I need to obtain the stresses and displacements. Next I want to couple the buckling analysis to the first step. I have define the second step however when I run the simulation I get the following error message:
DIFFERENTIAL STIFFNESS MATRIX IS COMPLETELY NULL. THE EIGENPROBLEM CANNOT BE SOLVED. IN A *BUCKLE ANALYSIS THE MOST LIKELY CAUSE IS THAT A NONZERO LOADING PATTERN WAS NOT SPECIFIED VIA *BOUNDARY, *CLOAD, *DLOAD, ETC
I have tried to use the restart attributes but I could not make it work.
Any help would be greatly appreciated.
Regards,
Ariyan





RE: Multi-Step Analysis
RE: Multi-Step Analysis
Thanks for your reply.
Yes I have applied the load for the buckling step. The only way to make the simulation work was replacing the first step by linear perturbation-buckle otherwise it does not let me to have the two step in conjunction with each other.
Thanks for your help in advance.
Regards,
Ariyan