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Selections under Definitions node vs Geometry node

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Hi everyone,

what difference does it make whether I am creating (and using) selections under the Definitions node vs under the Geometry node? There seem to be identical possibilities for both but it's impossible to combine selections from the Definition node with others from the Geometry node. What are the advantages and drawbacks of each variant? Is there a "better" one?

Thanks for your insights!

Cheers, Pascal


1 Reply Last Post 22.11.2022, 10:19 GMT-5
Magnus Ringh COMSOL Employee

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Posted: 2 years ago 22.11.2022, 10:19 GMT-5

Hi Pascal,

Yes, the selection options are similar when used from the Definitions node and when used in a Geometry sequence. The difference is that the former apply to the analyzed geometry, whereas the latter (for a Geometry sequence) apply to the geometry objects (blocks, cylinders, and so on). Those selections will then be "translated" into corresponding geometric entities (domain, boundaries, and so on) in the analyzed geometry, which is used for assigning material properties and physics, for example. So the choice is really about what would be more convenient for the further model setup. The selections in the Geometry sequence can also be used to define input objects in Boolean operations withing that sequency, for example.

For both categories, there are many settings and selection types that you can use to achieve the desired resulting selections for your model.

Best regards,

Magnus

Hi Pascal, Yes, the selection options are similar when used from the **Definitions** node and when used in a **Geometry** sequence. The difference is that the former apply to the analyzed geometry, whereas the latter (for a **Geometry** sequence) apply to the geometry objects (blocks, cylinders, and so on). Those selections will then be "translated" into corresponding geometric entities (domain, boundaries, and so on) in the analyzed geometry, which is used for assigning material properties and physics, for example. So the choice is really about what would be more convenient for the further model setup. The selections in the **Geometry** sequence can also be used to define input objects in Boolean operations withing that sequency, for example. For both categories, there are many settings and selection types that you can use to achieve the desired resulting selections for your model. Best regards, Magnus

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