Steady-State Problems in the CCL

Equations for the steady-state profdes fp and c can be obtained from the system (5.89) and (5.90) by chalking out the time derivatives. This approach, however, has the following drawback when the cell current is fixed, the boundary condition for fp at X = 0 is not known and it should be obtained as a result of iterations. 

The alternative approach is to solve a simpler equivalent system (4.156) and (4.55), which does not require iterations. The boundary conditions for Equations 4.156 and 4.55 are straightforward  

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