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Antenna Simulation on a platform

Hello,

I want to simulate a patch antenna on a platform (an aircraft). whenever i put the patch on aircraft body, it gives me error. Sometimes it says wrong specification of the medium for metallic triangles or sometimes it says segmentation rules violated, or triangles overlap. What I think is whenever two bodies intersect in feko it will give meshing error?I have been in this problem for a long time. Looking forward for answers.

Thanks.

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JIF

Hi ben,

You are correct; when triangles intersect or don't align where they touch, FEKO will give an error. FEKO 2018 has improved mesh checking in the solver and thus it is more likely to detect the intersecting / overlapping elements. You need to correct your model to ensure valid mesh connections. This is required in the MoM since basis functions need to created over triangles and this requires a valid mesh.

Altair Forum User

So, is there technique to put two objects together with each other. Because feko is gonna give error whatever I put on a platform. How can I solve this problem? I just want to put patch antenna on an aircraft and want to simulate it.

Mel

Here is an example of placing a patch.

Open platform.cfx
Import patch - tick Geometry box only, set prefix 'import_'
Select import_patch part and click on Align (on the Transform tab)
For 'Source Workplane' press together and hold Ctrl+Shift and left-click on center of ground plane of the patch.

Highlight the 'Destination Workplane' of the Align window and press the keys again to snap to the center of the platform plane.

See attached image for guidance.

(You may need to adjust the orientation (vectors) of the Destination to ensure the patch points into the desired direction.

The N-axis was normal to the patch for the Source Workplane so use the N-axis orientation again for the Destination)
Now Union all the parts.
Create Voltage source (this will now be the import_Port1) and solve.

I also attach the model files.

If the destination is a curved surface it will be more tricky, since the flat patch surface will not match the curved surface.

Perhaps then build a small flat section on the curved surface first. For example, project an ellipse just above the curved surface onto it. Then copy out the face that is created by the projection and sweep the face outwards to make a small flat surface. Then you can align the patch onto this new surface.

Attached the _alt.cfx model that shows the concept.

<?xml version="1.0" encoding="UTF-8"?>

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