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HFSS v12 error: Failure reading file for mode

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Newbie level 6
Jul 22, 2008
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I get an the following errors:
Adaptive solution setup, process hf3d error: Failure reading file for mode=(gives a mode number eg. 5)

right after the above error I get this one:
Unable to create child process: hf3d.

HFSS v12.0.0 is being ran on windows server 2008 enterprise edition.

Does anyone know how to fix this error?

Strange. I am getting "Failure reading file for mode = 4" "Unexpected internal software error code 0 with module id 0" in ver.13 when using Eigenmode solver.
In the past I have rarely used Eigenmode solver, and when used, I never seen this behavior.
So, what could be the cause of the error?

I do not remember what I did to get around this problem anymore. I posted that question back in 2009. I was new to HFSS at the time and I would guess I probably just set something up incorrectly. I do suggest if everything fails, try redoing the simulation from the start (do not copy and paste anything).

I found that this happens when using PML.
But I was using PML before and don't see the difference.

...recreating the model from the scratch...I should hang myself も(x_x)

Are you sure the PML is far enough away from the resonant structure to not significantly affect the results. Try a PEC boundary condition instead of the PML and make sure the simulation runs fine. This boundary should perturb the results slightly, but you can still make sure it works.


I used to get this error all the time before upgrading to HFSS 15. It occurred when trying to solve for modes which were spaced very far apart (in frequency). Try solving for a smaller number of modes, then create a new setup which solves for the remaining higher frequency modes.

Good Luck

My structure is not exactly resonant. It is periodic. PEC or PMC will surely give wrong waveguide modes which will destructively affect actual modes. PML is exactly what I need, but it crashes somehow.

In the past I had been trying a closed rectangular waveguide (PEC) or simple periodic objects in open-space (4 sides PML). And it was working fine.
Now I am simulating a periodic multilayer microstrip circuit and it crashes. Only when PML is created. I use PML wizard.

Thanks for suggestion! :thumbsup: I will try to pinpoint each mode selectively. Though, it is not very convenient...

The issue PlanarMetamaterials mentioned is an issue I had ran into, I just did not remember the error message. You do not need to do each mode individually, just less modes.

If you are trying to simulate a periodic structure (and want to generate beta-omega diagrams) you probably want it setup like this or this one

If you want to extract the effective properties of the the metamaterial you will want try something like that given here **broken link removed**. This edaboard thread has more on it

PML is an artificial material which is matched to free space and is extremely lossy. If too many of your boundary conditions are this material the eigenmode solver will likely not converge.

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