Use of dynamically adaptive grid techniques for the solutionof electrochemical kinetic equations Part 7. Testing of the finite-difference patch-adaptive strategy on example kinetic models with moving reaction fronts, in one-dimensional space geometry

摘要

The patch-adaptive strategy described in Part 5 proves to provide correct, firly efficient, and nearly automatic solutios to three representative example electrochemical kinetic models inone-dimensional space geometry, that exhibit difficult-to-resolve moving reaction fronts inthe electrolyte, away from the electrode. The models describe: double potential step experiments for a simple mechanism of electrochemically generated luminescence, linear potential sweep voltammetry for an EE-DISP mechanism with Nernstian charge transfers and a reversible homogeneous disproportionation reaction, and linear potential sweep voltammetry for an RRC-initiated electropolymerizaiton reaction scheme. The strategy dynamically create spatio-temporal grids that adaptively concentrate in the regions of the reaction fronts, without any a priori knowledge about their location. Numerical difficulties, such as electric current oscillations observed with the previously described adaptive moving grid technique in the case of moving reaction fronts, o not occur inthe present strategy. However, further wirk is needed to improve the performance of the strategy in the cases of reaction fronts associated with fast andirreversible scond-order homogeneous reactions, for which the computational costs are too large. Improvements are also desirable inthe case of the simulation of a rapidly moving reaction front occurring in the electropolymerization model, for which the strategy tends to provide incorrect front positions.