# Analysis of current flow at a component's edge

For one of my projects, I've designed the following component to deliver power to loads/circuits:

## Fig.1

The component in (Fig.1) breaks into 3 parts(a,b,c), my initial analysis of the current flow is shown in the diagram as (I), however, my concern is with the current flow from component a to b.

## Fig.2

How does the current flow in that region?

## Fig.3

I tried to break down 3 possible current directions on that edge, which one would be most accurate to describe the current's flow?

The reason I am analyzing that segment, is because of the possible magnetic field associated from this component.

What makes sense to me is a magnetic field that literary wraps around the component, however, a field produced by the sub-current (1) in Fig.3 seems unlikely.

Update:

• FEA simulation via ANSYS Maxwell:

Fig.4

Fig.5

• The conduction band charges will have a nearly completely uniform distribution in the metal shape. There will be a slight excess at the surface, but otherwise very nearly uniform distribution throughout. All the way to the corners. A very, very small number of charges will "stick" at some corners in order to accelerate the charges around the bends. Like negative-gravity, so to speak. (Charges don't turn without a reason.) Plus the needed charge gradient along its length. Can you now work out the drift velocity implications given the shape? What happens if the current increases a lot? – jonk Nov 25 '17 at 20:58
• I will attempt to. A uniform distribution is what I intentionally thought so as well.However, consider my point of confusion: The driving force for the charges is perpendicular to the sub-current(1) in Fig.3, how can current be driven to that region with no driving force towards the corners? Maybe that's my limitation in understanding current flow. – Pupil Nov 25 '17 at 21:02
• There is a very slight charge gradient along the length in order to accelerate the charges, as well. You can actually detect this if you set up a high voltage DC supply and a long wire. Use a pith ball. In the center, the pith ball does nothing. But at each end it is attracted and then instantly repelled as it accumulates some of those charges (which are immediately replaced, of course.) – jonk Nov 25 '17 at 21:04
• I think that there is a big missunderstanding in the intepretation of your question about the scale of your geometry. What are the order of magnitude of the involved variables: nm,um,mm,meters ? Concerning the currents : fA,uA,mA,A,kA ? Do you care about noise under nA ? Personnaly I think that you deal with electrotechnics. – andre314 Nov 26 '17 at 10:38
• Andre, the magnitude should be the standard, A and m. What noise? – Pupil Dec 3 '17 at 20:25