Learning Forum

[xh19363]

Hello everyone

I am using parameter sweep in FDTD and I don't understand quite well the numbers that are appeared in the job manager window about the autoshutoff level . In the FDTD window, the autoshutoff level is set as following

From this page, Analyzing Simulation Results - Result Accuracy - Auto Shutoff Level, I found the following explanation

"However, the simulation might end sooner if the autoshutoff level is reached. The current energy level of the system relative to its peak value during the simulation is also shown in the job manager window as the auto shutoff level."

1)  What is exactly the autoshutoff level numbers that are appeared on job manager window? Is it a ratio?

2) Why there is much variety of those numbers such are the first is 0.000168248, the third is 3.01966e-6 and the fifth is 0.12061? Should those numbers be similar? 

3) Do the autoshutoff level numbers mean something about my simulation (e.g. is there any error)?

4)Why the first and third sweep have the same progress which is 18% but they have different autoshutoff level numbers?

Best Regards

[Guilin Sun]

A1: it is the percentage of the energy inside the simulation volume at any moment relative to the original injected energy.

A2: it is due to resonance. You can use a time monitor and then check the spectrum after the simulation terminates.

A3: somewhat: since the time domain monitor uses Fourier transform from the time signal to the CW result, we need to simulate long enough to let the signal decay completely for accuracy.

A4: It depends on each individual device: each time the parameter changes it will have different performance (or they are different devices), such as resonance. It is normal.