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How to change properties before second step simulation

Posted 5 juil. 2012, 10:47 UTC−4 Chemical Reaction Engineering, Parameters, Variables, & Functions Version 4.2a 1 Reply

Oscar Vera
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Hi,

I am modeling the electrodialysis effect in two sqare channels, one being the dilute channel and the other one the concentrate channel.

My problem is that many of my properties (density, viscosity, diffusion, etc. ) depend on the concentration in each channel. I have the initial concentration of both channels. My geometry is very small, and simulating the process one time is not a problem. I loose a little bit of concentration in the dilute channel and I gain a little bit on the concentrate channel, so I assume that the properties calculated with the initial concentration are adequate.

Now, I am "recirculating" my electrolyte through my channels, the diluted electrolyte goes in the dilute channel and the concentrated electrolyte goes in the concentrated channel. I do this defining some ODE's in the outlet of my channels and using the variable created as inflow. Since I am doing a time dependent simulation, at some point, the concentration in the dilute and in the concentrate channel will be completely different from the initial concentration, so I need to recalculate my properties with the new concentration.

How can I recalculate my properties before doing the second step of my simulation?

I hope I was clear and you can help me.



Oscar

1 Reply Last Post 5 mai 2016, 14:14 UTC−4
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Hello Oscar Vera

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Maria Elena Orduna Alegria
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Posted: 9 years ago 5 mai 2016, 14:14 UTC−4
Hi Oscar,

I`m curently working on a electrodialysis model, and I have a problem with the membranes and maybe you can help me

Which module did you use to specify the membranes?
I`m using pointwise contraints in secondary current distribution module from electochemistry. But when I run it I have an error saying "Failed to evaluate variable Jacobian". And Im using a 3D model.

So I`m wondering if there is any other way to put the membranes?

Thanks for your help in advance



Hi Oscar, I`m curently working on a electrodialysis model, and I have a problem with the membranes and maybe you can help me Which module did you use to specify the membranes? I`m using pointwise contraints in secondary current distribution module from electochemistry. But when I run it I have an error saying "Failed to evaluate variable Jacobian". And Im using a 3D model. So I`m wondering if there is any other way to put the membranes? Thanks for your help in advance

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