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Problem with boundary settings in electrophoresis

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Hello, everyone.
I am currently doing simulation regarding to electrophoretic polarisation of chemical species in a channel.

There are two conditions which i am both having problems in.

1.a microchannel with no fluid flow but with initial value of 0.1mol/m3 chemical species. inflow and outflow condition were set at left and right boundaries.
everytime i address a initial value to the channel. i get no electrophoretic polarization.
Is there something i miss?
Is there some flux boundary condition required?

2.I want to simulate electrophoretic polarization of a chemical species in a domain. like in a "box"
in this case i thought using inflow and outflow as boundary conditions for the left and right boun daries would be incorrect?
but if i don't set any boundaries there would be errors.

I suspect i have to add BCs of fluxes?

I have absolutely no clue on how to set the boundary conditions in order for the simulation to work.

I am really greatful if you could share your experience and opinions

A lot of thanks in advance.

Best,
Paul

1 Reply Last Post 2012年3月29日 GMT-4 03:08

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Posted: 1 decade ago 2012年3月29日 GMT-4 03:08
Hello everyone.
I still couldn't get my head around this problem.
I created a electric current and transport of diluted species problem like this.
the chemical species i have is potassium ion at a concentration of 5.33mM.

The problem i have is that i want to simulate the potassium polarization and concentration to the anode.
But i don't know what BC setting i should go with.
Using inflow and outflow don't seem right.
and without specifying inflow and outflow, there would be warning message.
if not, the simulation would still look strange, because in the first time step there should be even concentration of 5.33 in the whole channel.


How do i set the BC settings so i can simulate the polarization and concentration like in a box?
is it have something to do with the flux? I don't really understand the flux BC settings.

Many thanks to you

Paul
Hello everyone. I still couldn't get my head around this problem. I created a electric current and transport of diluted species problem like this. the chemical species i have is potassium ion at a concentration of 5.33mM. The problem i have is that i want to simulate the potassium polarization and concentration to the anode. But i don't know what BC setting i should go with. Using inflow and outflow don't seem right. and without specifying inflow and outflow, there would be warning message. if not, the simulation would still look strange, because in the first time step there should be even concentration of 5.33 in the whole channel. How do i set the BC settings so i can simulate the polarization and concentration like in a box? is it have something to do with the flux? I don't really understand the flux BC settings. Many thanks to you Paul

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