Fractional step algorithm for estuarine mass transport

A successful and economical fractional step algorithm for the convection‐dispersion‐reaction equation is described. Exact solutions are adopted for the reaction and convection steps, the latter by the introduction of a moving co‐ordinate system. The dispersion step uses an optimized finite difference algorithm which specifically accommodates the grid non‐uniformity. The excellent performance of the algorithm is confirmed by numerical experiments together with computations of the Fourier response and integrated square error characteristics.