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Residence time in the particle tracing module

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I ran a simulation of a polymeric solution inside an extrusion die by using laminar flow and carreau model. Afterwards, I implemented the particle tracing module, beacuse I am interested in the residence time which is the time a particle takes to exit the die.

Does anybody know how to add the auxiliary dependent variable: d(rp)/dt = 1 in the particle tracing module?

Somebody told me that this will solve the additional ODE per particle, and rp is the residence time.

3 Replies Last Post 18 déc. 2013, 09:39 UTC−5
Daniel Smith COMSOL Employee

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Posted: 1 decade ago 23 févr. 2012, 08:47 UTC−5
Hi, you simply right click on the "Particle Tracing for Fluid Flow" interface and chose "Auxiliary dependent variable".
Hi, you simply right click on the "Particle Tracing for Fluid Flow" interface and chose "Auxiliary dependent variable".

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Posted: 1 decade ago 17 déc. 2013, 21:23 UTC−5
Hi,I want to ask one question about the residence time in the particle tracing module.
I have chosen "Auxiliary dependent variable",and set to"with respect to time"
But after study ,when I want to show the data of every particle by histogram
it says"failed to evaluate expression
-expression: model1.rp
-plot:hist1(histogram)"
Should I define a varaiable before study in Defination?
I will be grateful for your help.

Hi,I want to ask one question about the residence time in the particle tracing module. I have chosen "Auxiliary dependent variable",and set to"with respect to time" But after study ,when I want to show the data of every particle by histogram it says"failed to evaluate expression -expression: model1.rp -plot:hist1(histogram)" Should I define a varaiable before study in Defination? I will be grateful for your help.

Daniel Smith COMSOL Employee

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Posted: 1 decade ago 18 déc. 2013, 09:39 UTC−5
Hi, the Histogram plot needs to have its "Data set" pointing to the "Particle 1" data set.

Dan
Hi, the Histogram plot needs to have its "Data set" pointing to the "Particle 1" data set. Dan

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