![Divergence rule](https://www.mathworks.com/matlabcentral/answers/uploaded_files/739344/Divergence%20rule.png)
How do I re-write the Nernst-Planck equation in PDE Toolbox form?
4 views (last 30 days)
Show older comments
Hiya, really struggling with re-arranging the Nernst-Planck equation to specify coefficients:
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/690563/image.jpeg)
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/690568/image.jpeg)
In the form that PDE Toolbox requires:
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/690573/image.jpeg)
I understand that:
m = 0
d = 1
f = 0
But besides that I have no idea how to specify co-efficients 'a' and 'c' to form this equation, due to the addition of the electric field component.
Any wisdom much appreciated!!
0 Comments
Answers (1)
Tanmay Das
on 15 Sep 2021
Hi,
You can use the following rule to solve the Nerst-Plank equation and reduce it to a form required by PDE toolbox.
![Divergence rule](https://www.mathworks.com/matlabcentral/answers/uploaded_files/739344/Divergence%20rule.png)
1 Comment
Peifeng Su
on 10 May 2023
Hi, I also have the same question. Except in my ase, the electrical feild can be regarded as constant
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/1379919/image.png)
Similarly, i don't understand how to consider the second term in the right side in that form. Can you please explain more about the product rule? Are there part of pdepd function?
See Also
Categories
Find more on Eigenvalue Problems in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!