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Calculating % volume of 3D domain encompassed by a surface

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I am running version 4.0a.

I have a system with transient diffusion of dilute species (implemented via the 'transport in dilute species' physics) throughout a cylindrical domain. To visualise my results at a given time t, I have made a 3D plot group and applied a filter for concentration of one of my species (lactate, denoted LAC) with the following expression:

1*(LAC<=0.05)

This gives me results as expected, i.e. a surface plot of regions within my domain where the concentration is less than or equal to 0.05 mol/m3

I now want to know the percentage of my overall domain which is contained within this surface plot. In other words:
"what percentage of my domain volume has a concentration of LAC<=0.05mol/m3?"

I know the volume occupied by my entire domain, so is there a way of evaluating the volume 'encompassed' by the surface? If I can evaluate this quantity through time, then that would be ideal.

Hope my query is clear, and thank you in advance for your help,

Karan


1 Reply Last Post 2013年11月22日 GMT-5 02:28
Gunnar Andersson COMSOL Employee

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Posted: 1 decade ago 2013年11月22日 GMT-5 02:28
You can calculate the fraction as follows:

1. Results > Derived Values > Integration: Add a Volume Integration feature.
2. Change the selection to All domains.
3. Change the expression to (LAC<=0.05)/volume_of_domain where you replace "volume_of_domain" with the volume, which you write that you know.
4. Click on Evaluate in the toolbar.
You can calculate the fraction as follows: 1. Results > Derived Values > Integration: Add a Volume Integration feature. 2. Change the selection to All domains. 3. Change the expression to (LAC

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