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Geometry present or not depending on a parameter
Posted Feb 8, 2013, 11:44 a.m. EST Geometry Version 4.3a 1 Reply
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Hi!
I am trying to create a geometry that will have certain elements appear or disappear depending on a variable. For example: I have a variable "var1" that can take the values of 1 or 2. I have a geometry that hast a plate with a hole in the middle (in 2D, so it would basically look like a rectangle with a circle in the middle). I want to be able to have COMSOL build the geometry with the circle if I input 1 for "var1" and to build the geometry with just the rectangle is I input 2 for "var1"
Thank you very much for your help.
Francesco
I am trying to create a geometry that will have certain elements appear or disappear depending on a variable. For example: I have a variable "var1" that can take the values of 1 or 2. I have a geometry that hast a plate with a hole in the middle (in 2D, so it would basically look like a rectangle with a circle in the middle). I want to be able to have COMSOL build the geometry with the circle if I input 1 for "var1" and to build the geometry with just the rectangle is I input 2 for "var1"
Thank you very much for your help.
Francesco
1 Reply Last Post Feb 8, 2013, 3:17 p.m. EST
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Posted:
1 decade ago
Francesco-
First off, be sure to use a Global>Parameter definition and not a variable definition as variables in COMSOL aren't allowed to be used in the Geometry node.
As to parameterizing the existance and non-existance of a hole, I have had success doing this by using the Array function and making the array size a function of a parameter that can be 0 if you don't want the object present.
Be advised, if you are performing a boolean difference operation on the array object you can't completely remove the object or you will get a geometry error. See the attached mph file for a workaround. Set parameter array_x to 1 to have no hole in the square. Set parameter array_x to 2 to have a hole in the square.
Regards,
Josh Thomas
AltaSim Technologies
First off, be sure to use a Global>Parameter definition and not a variable definition as variables in COMSOL aren't allowed to be used in the Geometry node.
As to parameterizing the existance and non-existance of a hole, I have had success doing this by using the Array function and making the array size a function of a parameter that can be 0 if you don't want the object present.
Be advised, if you are performing a boolean difference operation on the array object you can't completely remove the object or you will get a geometry error. See the attached mph file for a workaround. Set parameter array_x to 1 to have no hole in the square. Set parameter array_x to 2 to have a hole in the square.
Regards,
Josh Thomas
AltaSim Technologies
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