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chunlong Tan September 19, 2022 09:01

Time step about forced harmonic simulation
 
Dear all,

when I chosen Harmonic->Fluid Structure->Mechanical Coupling->Modal->Forced motion to conduct an flutter analysis. I found that there was no imformation about iteration time step. I'm wondering if this type of simulation is not related to the time step, or if I didn't find where to set the time step.

Kind regards,
Chunlong

Wout Poncelet September 30, 2022 10:43

Time step about forced harmonic simulation
 
Dear Chunlong,

Given that you're performing a flutter analysis and you mention the harmonic, I assume you're running a NLH simulation? Is my understanding correct?

In that case, there is no need to specify a time step (just a CFL number). The NLH method will solve the NS-equations in the frequency domain. Once your simulation is converged, you will be able to reconstruct your solution in space and time, here you can specify the time step and the number of time steps you want to reconstruct.

The imposed forced motion, in case of a NLH simulation, can be constant in time or defined with a given frequency/mean value/IBPA/Real and imaginary part.

I hope this may help you.

With best regards,
Wout Poncelet

chunlong Tan October 13, 2022 02:22

Time step about forced harmonic simulationReply to Thread
 
Dear Wout,

Thank you, your answer has completely solved my confusion.

Kind regards,
Chunlong


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