Limitations of empirical sediment transport formulas for shallow water and their consequences for swash zone modelling. Issue 1 (2nd January 2017)

• Record Type: Journal Article
• Authors: Li, Wei; Hu, Peng; Pähtz, Thomas; He, Zhiguo; Cao, Zhixian
• Is Part Of: Journal of hydraulic research. Volume 55:Issue 1(2017)
• Page Start: 114
• Page End: 120
• Publication Date: 2017-01-02
• Subjects: Phase-resolving swash model -- sediment transport -- shallow water -- swash zone; Hydraulics -- Research -- Periodicals; Hydraulic engineering -- Periodicals; Hydraulic engineering; Electronic journals; Periodicals; 621.2
• DOI: 10.1080/00221686.2016.1212942
• Languages: English
• ISSNs: 0022-1686

Abstract

ABSTRACT: Volumetric sediment concentrations computed by phase-resolving swash morphodynamic models are shown to exceed unity minus porosity (i.e. the maximal physically possible concentration value) by up to factor of 10 5 when using standard expressions to compute the sediment transport rate. An ad hoc limit of sediment concentration is introduced as a means to evaluate consequences of exceeding physically realistic concentration by standard expressions. We find that implementation of this ad hoc limit strongly changes the quantitative and qualitative predictions of phase-resolving swash morphodynamic models, suggesting that existing swash predictions are unreliable. This is because standard expressions inappropriately consider or ignore the fact that the shallow swash water depth limits the storage capacity of transported sediment.