Author(s): W. M. Kranenburg; T. van der Kaaij; H. van den Boogaard; R. E. Uittenbogaard; Y. M. Dijkstra
Keywords: No keywords
Abstract: This paper presents an instrument to determine salt flux components and equivalent dispersion rates from 3D numerical model results for estuarine salinity. A spatial decomposition decomposes velocity and salinity in cross-sectional averages and variations quantifying contributions of cross-sectional means and variations to the total mean salt flux. A temporal decomposition separates the effect of storm-events and tidal components by processing velocity and salinity signals with Godin filtering together with harmonic analysis. From the spatial decomposition equivalent dispersion coefficients are computed, and applied in a 3D-1D numerical model comparison. This shows nearly complete reproduction. We conclude that the salt flux decomposition instrument provides valuable support in interpretation of 3D-model results by giving insight in the relative importance of various physical mechanisms, and in verification and improvement of 1D-models for quick assessments and derivation of statistics. The tool is available and in principle applicable in combination with any 3D-numerical model.