Pore diffusion - radial differential equation

Peiwen Lau

2013 2 13

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8 次查看（30 天）

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Hey guys, I'm trying to solve the pore-diffusion kinetic problem, but do not know where to start with. Someone in this community has used the pdepe in Matlab to solve the equation, but the details are not available. Could you please help me with this? The equation looks like this:

Ep*(dC/dt) = Ep*D*(d^2C/dr^2 + 2*dC/(r*dr)) - (1-Ep)*dq/dt

in which hte local equilibrium and differentiating the Langmuir equation wrt t yields:

dq/dt = dC/dt*(qm*Kd/(C+Kd)^2)

substituting gives:

[Ep+(1-Ep)*qm*Kd/(C+Kd)^2)]*dC/dt = Ep*D*(d^2C/dr^2 + 2*dC/(r*dr))

with initial condition t=0, c=0 and boundary conditions r=0, dC/dr =0, and r=R, C=CR where CR is the concentration in equilibrium with q* obtained from the Langmuir equation.

Thanks a mil