Learning Forum

[Fady Elshazly]

Hello,

 

I am solving model explicitly and the input motion has a time step of 0.005 sec. I am trying to record the nodout in ASCII database at dt=0.01 sec and dt=0.0001 sec. Both models give different results. Is the nodout dt used in input interpolation and then used in the analysis? or what would make this difference. 

 

 

Thanks 

[Andreas Koutras]

Hello, output cannot be generated at time intervals less than the timestep size of the analysis. The smaller output time interval can output a higher frequency of the response. However, the results at the same time instances should be the same in the two cases.

[Fady Elshazly]

The analysis time step is 1*10-5 which is smaller than the two cases.  The dt i am using to generate the output is used only for the nodeout and is smaller than the one for the d3plot. can this cause the results difference? 

[Andreas Koutras]

Hello Fady,

Please see the above reply:

The smaller output time interval can output higher frequencies of the response. However, the results at the same time instances should be the same in the two cases.

[Fady Elshazly]

Thank you so much