Problem of failing to start simulation sometimes


I used the trial version of FDTD solution. Sometimes when I start the run button, the software cannot start multi-threads computing. Each time I need quit the simulation and restart it again and again till it triggers the multi-cpu. I donot know if this is problem of trial version or other problems.

Additional question, during the simulation, normally software shows the aprroximate simulation time, however, in my most case, my simulation stops much earlier before the suggested time. The reason for me is alway multi-threads computing stops after starting several minutes. I donot know, it is problem of my computer or trial problem or setting of my cases.

I use FDTD solution to simulate the scattering from metallic grating with area about 5 µm * 5 µm.

Thank you very much in advance.


Dear @yang

Sorry for any inconvenience.

There is no difference between trail and licensed version of the software except, of course, in the licensee agreement. You should be able to check the full capability of the software in the trial version.

Can you please elaborate more on how you are setting up your CPUs or processors? For example, I have a 12 core CPU and can select any number of processors (as long as it does not exceed the total available number) from resources tab. As is shown in the screenshot below, I am using 10 cores to run simulations:

It is recommended to click on Run tests before running simulations and make sure that the processors are set properly.

Regarding your second question: Simulation will automatically stop if the available energy in the FDTD region goes below the auto shutoff level. To learn more about this feature and how to modify it, please take a look the link below:

I hope I could answer your questions.