Use the Sacrificial Anode Surface node to model dissolving metal electrodes in corrosion protection applications. A Sacrificial Anode Surface can only be applied to exterior boundaries to Electrolyte domains. The node is only available when a Secondary Current distribution type has been chosen on the top node.

In time-dependent simulations, the node solves for a capacity (SI unit: C/m2) degree of freedom to keep track of the total amount of passed charge along the boundary.

The actual dissolution rate is defined by the Electrode Reaction subnodes. By enabling Set current density to zero at depletion, all current densities are set to zero when the capacity goes to zero, using a smoothed step function. The Size of transition zone value sets the relative capacity for which the smoothing starts close to depletion.

Enable Add tangential diffusion to improve convergence by smoothing out local capacity gradients along the boundaries.

The potential in the electronic phase is used by the Electrode Reaction subnodes in the kinetics expressions.

See the Electrode Surface node.

See the Electrode Surface node.

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