Discussion Forum

So far, I've done modeling by drawing cylinder shape fiber and using Fitzhugh-Nagumo equations on PDE mode.
The paper i referred to is as follow.
"3D-Simulation of Action Potential Propagation in a Squid Giant Axon"

Somehow, when i follow the instruction as written, especially on the Subdomain setting> Init section, i couldn't see the propagating signal effect on the animated result.
u (t )=V *((x+d)> 0 ) *(z+d > 0 ))
u (t )= nu *(( x+d)>0 )* (z+d > 0))

As i delete the (x+d) terms on both eq and arbitrarily substitute (z+d) terms with (z-25)>0 in first eq, and (-z-25)>0 in second eq, i could see the propagating effect, but not exactly what i was expecting.
I want the fiber to be stimulated at the specific section(which will appear as red and thin color band) and then propagate to both side.

Second, when coupling with electrostatic module, the boundaries of the axon are chosen as electric potential sources with the coupling variable u1(V = u1) in the paper. I wonder if i could just plug in the u1(variable from PDE equation) in the boundary setting>electrical potential value.

The animated file is attached below.
The result also seems to be totally different if changing time stepping time(for example, time(0,1,100) to time(0,10,100)
I will be really appreciate if i could get any feedback from you. :)
Thanks!