Hi everybody,
I am confused by a very simple electrostatic problem illustrated in the attached drawing. My model (2D) consists in a first circle (1) defining the limits of the computation domain. A surface charge boundary is applied on a second circle (2) which is centered on the same point than circle 1. A third circle (3) is also present inside circle 1.
I simulated two situations: in the first case, a ground boundary is applied on circle 1 while a floating potential boundary is applied on circle 3. In the second case, this is the opposite: ground is on circle 3 while circle 1 is a floating potential.
The electrical field computed by Comsol is different in these two situations. From my basic understanding of electrostatics, I expected the two situations to be totally equivalent one to the other, i.e. the electrical field does not depend on which of the two equipotential surface the reference potential is set. Is it a numerical related issue or am I incorrect in my understanding?
I am confused by a very simple electrostatic problem illustrated in the attached drawing. My model (2D) consists in a first circle (1) defining the limits of the computation domain. A surface charge boundary is applied on a second circle (2) which is centered on the same point than circle 1. A third circle (3) is also present inside circle 1.
I simulated two situations: in the first case, a ground boundary is applied on circle 1 while a floating potential boundary is applied on circle 3. In the second case, this is the opposite: ground is on circle 3 while circle 1 is a floating potential.
The electrical field computed by Comsol is different in these two situations. From my basic understanding of electrostatics, I expected the two situations to be totally equivalent one to the other, i.e. the electrical field does not depend on which of the two equipotential surface the reference potential is set. Is it a numerical related issue or am I incorrect in my understanding?