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Integration on a volume using a parameter

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Dear COMSOL colleagues,

I am simulating the flow in a biological chamber, using laminar flow and transport of diluted species to simulate the convection and diffusion of oxygen in the chamber, as well as the consumption of oxygen by the cells inside it.

After running my simulation, I would like to have a distribution of oxygen.
What I can do is use a step function to calculate the volume inside the chamber above a certain threshold concentration (i.e. 70% of the chamber is below 0.3mol/m3, 60% is below 0.2mol/m3, 50% is below 0.1mol/m3).
But using the Volume Integration in Derived Values, I always need to specify this threshold (0.3 - 0.1 mol/m3).
That s why I would like to make a Volume Integration but for a range of thresholds (way more than what I could manually implement) to be able to plot Volume = function(threshold concentration).

Is there a way to make a 1D plot using some kind of integration function with a parameter that would vary ?

Thank you
Pierre

1 Reply Last Post 03.02.2015, 15:11 GMT-5
Jeff Hiller COMSOL Employee

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Posted: 10 years ago 03.02.2015, 15:11 GMT-5
Hello Pierre,
It's not the most elegant of solution, but check out the attached file; I think it does what you want.
I added a second study that runs a parametric sweep but does not actually solve any equations. This sweep forces the evaluation of the variable "volumebelowthreshold" for a bunch of values of the threshold. Since no equation is solved in that study, this is numerically very inexpensive.
I hope this helps.

You could certainly achieve the same through some programming with LiveLink for MATLAB, or in a method in an application.
Best,
Jeff
Hello Pierre, It's not the most elegant of solution, but check out the attached file; I think it does what you want. I added a second study that runs a parametric sweep but does not actually solve any equations. This sweep forces the evaluation of the variable "volumebelowthreshold" for a bunch of values of the threshold. Since no equation is solved in that study, this is numerically very inexpensive. I hope this helps. You could certainly achieve the same through some programming with LiveLink for MATLAB, or in a method in an application. Best, Jeff

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