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Help: simple simulation of the concentration battery

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Hello everyone. I have been plagued by the simulation of the concentration battery recently. the model like this:https://i.loli.net/2018/12/16/5c163d722b52a.png WHO CAN HELP ME I am truely thankful my email: chenxu2656@gmail.com


2 Replies Last Post 17.12.2018, 06:12 GMT-5

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Posted: 6 years ago 17.12.2018, 06:04 GMT-5

I have tried to model an ion-exchange membrane with very little of success. The problem is the fixed charges in the membrane. Only with relatively low fixed charge density I have managed to find a solution. Then I made a model using the Nernst-Planck equation only, and put for the mobility of the fixed charge a negligible value (not zero) of 1e-60. Then I got a result but I would not bet my life on it...

We have a published a book "Ionic Transport Processes"

https://global.oup.com/academic/product/ionic-transport-processes-9780198719991?cc=fi&lang=en&

where the problem is treated explicitly. It requires solving a transcendental equation. But assuming a perfect ion-exchange membrane, the transport number of the counter ion is 1 and that of co-ion zero. That simplifies the analysis hugely, and an analytical solution can be reached.

BR Lasse Murtomäki

I have tried to model an ion-exchange membrane with very little of success. The problem is the fixed charges in the membrane. Only with relatively low fixed charge density I have managed to find a solution. Then I made a model using the Nernst-Planck equation only, and put for the mobility of the fixed charge a negligible value (not zero) of 1e-60. Then I got a result but I would not bet my life on it... We have a published a book "Ionic Transport Processes" https://global.oup.com/academic/product/ionic-transport-processes-9780198719991?cc=fi&lang=en& where the problem is treated explicitly. It requires solving a transcendental equation. But assuming a perfect ion-exchange membrane, the transport number of the counter ion is 1 and that of co-ion zero. That simplifies the analysis hugely, and an analytical solution can be reached. BR Lasse Murtomäki

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Posted: 6 years ago 17.12.2018, 06:12 GMT-5

https://global.oup.com/academic/product/ionic-transport-processes-9780198719991?cc=fi&lang=en&

thank you very much ,I'll go back and read the book you mentioned

>https://global.oup.com/academic/product/ionic-transport-processes-9780198719991?cc=fi&lang=en& thank you very much ,I'll go back and read the book you mentioned

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