MORPHODYNAMIC UPSCALING WITH THE MORFAC APPROACH

Roshanka Ranasinghe, Cilia Swinkels, Arjen Luijendijk, Judith Bosboom, Dano Roelvink, Marcel Stive, Dirkjan Walstra

Abstract


The Morphological Acceleration Factor (MORFAC) approach for morphodynamic upscaling enables the simulation of long term coastal evolution. However the general validity of the MORFAC concept for coastal applications has not yet been comprehensively investigated. Furthermore, a robust and objective method for the a priori determination of the highest MORFAC that is suitable for a given simulation (i.e. critical MORFAC) does not currently exist. This paper presents some initial results of an ongoing, long-term study that attempts to rigorously and methodically investigate the limitations and strengths of the MORFAC approach. Based on the results of a numerical modelling exercise using the morphodynamic model Delft3D, the main dependencies and sensitivities of the MORFAC approach are investigated. A criterion (based on the CFL condition for bed form migration) for the a priori determination of the critical MORFAC is also proposed.

Keywords


Morphodynamic modelling; MORFAC; Delft3D; long term coastal evolution

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