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Solving Pooisson/Laplace Equation for Multi-Electrode Array
Posted Nov 4, 2013, 11:28 a.m. EST Low-Frequency Electromagnetics, Mesh, Studies & Solvers Version 4.3b 1 Reply
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Dear All,
Iḿ trying to use Comsol to solve the laplace equation within a 3-D space.
This 3D space is limitted by a block of 8000x8000x500um.
The Top-Plane xy,500 should be at ground (V=0V).
The potentials at the side (x,4000,z), (x,-4000,z), (4000,y,z),(-4000,y,z) should form a zero-flux boundary with dV/dn=0.
on the electrodes with diameter D/2 and spacing S there should be a current flowing with dV/dn=i/(pi*(D/2)^2).
I build this within the attached model.
The solver cannot solve this problem. Iḿ getting an error that the threshold is reached.
Could anyone help please?
It is also possible that I did some error within the boundary definition or the choice of the physics.
If there could anyone check I would be really greatful.
kind regards
Iḿ trying to use Comsol to solve the laplace equation within a 3-D space.
This 3D space is limitted by a block of 8000x8000x500um.
The Top-Plane xy,500 should be at ground (V=0V).
The potentials at the side (x,4000,z), (x,-4000,z), (4000,y,z),(-4000,y,z) should form a zero-flux boundary with dV/dn=0.
on the electrodes with diameter D/2 and spacing S there should be a current flowing with dV/dn=i/(pi*(D/2)^2).
I build this within the attached model.
The solver cannot solve this problem. Iḿ getting an error that the threshold is reached.
Could anyone help please?
It is also possible that I did some error within the boundary definition or the choice of the physics.
If there could anyone check I would be really greatful.
kind regards
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1 Reply Last Post Nov 5, 2013, 5:56 a.m. EST
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Posted:
1 decade ago
Dear Ms. Rieger,
I had a quick glance at your model and noticed that you did not use "Constraint 1" correctly. Please have a look at the equation, which reads "R=0". So, in order to achieve u=0, you need to enter your dependend variable "u" in the expression field for "R". Maybe the "Dirichlet Boundary Condition" is more intuitive for you.
Best regards
Bettina Schieche
I had a quick glance at your model and noticed that you did not use "Constraint 1" correctly. Please have a look at the equation, which reads "R=0". So, in order to achieve u=0, you need to enter your dependend variable "u" in the expression field for "R". Maybe the "Dirichlet Boundary Condition" is more intuitive for you.
Best regards
Bettina Schieche