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Boundary Mode Analysis Undefined Variable
Posted Sep 30, 2014, 11:17 a.m. EDT RF & Microwave Engineering Version 5.1 3 Replies
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Simple waveguide problem. I make a rectangular block of air, 2 cm x 1 cm x 10 cm surrounded by the default PEC boundaries. Ports at each end. Ports both set to Numeric. Add study -> Boundary Mode Analysis Frequency domain. I set the frequency of the mode analysis and frequency domain to be 10 GHz. Everything else defaults. I click compute. Bang:
Undefined value found.
- Detail: Undefined value found in the equation residual vector.
There are 1 degrees of freedom giving NaN/Inf in the vector for the variable comp1.emw.S2x.
at coordinates: (0,0,0), ...
- Feature: Stationary Solver 1 (sol1/s1)
What's this undefined value? If I make one of the ports rectangular, no error. But both numeric, Undefined value. What's the deal here? Obviously I'm missing something obvious with regard to how boundary mode analysis and numeric ports work. What is it? The docs on this topic (as usual) are pretty thin.
Undefined value found.
- Detail: Undefined value found in the equation residual vector.
There are 1 degrees of freedom giving NaN/Inf in the vector for the variable comp1.emw.S2x.
at coordinates: (0,0,0), ...
- Feature: Stationary Solver 1 (sol1/s1)
What's this undefined value? If I make one of the ports rectangular, no error. But both numeric, Undefined value. What's the deal here? Obviously I'm missing something obvious with regard to how boundary mode analysis and numeric ports work. What is it? The docs on this topic (as usual) are pretty thin.
3 Replies Last Post Apr 11, 2016, 11:55 p.m. EDT
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Posted:
1 decade ago
SOLVED.
It appears that boundary mode analysis steps need to be run for all ports within the same Study node. I had my analyses for my ports as separate studies and they don't "talk". So if,
say, you have two ports, you first add a study from the wizard that has boundary mode analysis. The
node should look like this.
Study
Step1 Boundary Mode Analysis
Step2 Frequency Domain
Now you need to add another Boundary Mode Analysis step. You can do this by right clicking
the Study, and under Study Steps find Boundary Mode Analysis and add it. But this will add it to
the end of the study as Step 3. Wrong.
Study
Step1 Boundary Mode Analysis
Step2 Frequency Domain
Step3 Boundary Mode Analysis
Drag it up to become step 2, and it will work.
Study
Step1 Boundary Mode Analysis
Step2 Boundary Mode Analysis
Step3 Frequency Domain
Another COMSOL mystery solved.
It appears that boundary mode analysis steps need to be run for all ports within the same Study node. I had my analyses for my ports as separate studies and they don't "talk". So if,
say, you have two ports, you first add a study from the wizard that has boundary mode analysis. The
node should look like this.
Study
Step1 Boundary Mode Analysis
Step2 Frequency Domain
Now you need to add another Boundary Mode Analysis step. You can do this by right clicking
the Study, and under Study Steps find Boundary Mode Analysis and add it. But this will add it to
the end of the study as Step 3. Wrong.
Study
Step1 Boundary Mode Analysis
Step2 Frequency Domain
Step3 Boundary Mode Analysis
Drag it up to become step 2, and it will work.
Study
Step1 Boundary Mode Analysis
Step2 Boundary Mode Analysis
Step3 Frequency Domain
Another COMSOL mystery solved.
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Posted:
9 years ago
I got the same error and I also tried above solution but still it is giving the same error.Help me if you can.
Thank you in advance.
Thank you in advance.
Please login with a confirmed email address before reporting spam
Posted:
9 years ago
I got the same error and I also tried above solution but still it is giving the same error.Help me if you can.
THX!
THX!