Author(s): Gregory Lawrence
Linked Author(s): Gregory Lawrence
Keywords: Two-layer flows Internal hydraulic jumps Kelvin-Helmhotz instabilities Holmboe Instabilities Turbulence Mixing
Abstract: Mixing in two-layer flows is determined by the interaction of the internal hydraulics of those flows and the hydrodynamics of sheared density interfaces. Laboratory experiments for six different configurations have been analysed: unidirectional flow over topography (Lawrence, 1993); exchange flow over topography (Zhu & Lawrence, 2001); exchange flow through a horizontal channel (Tedford et al. 2009); exchange flow through an inclined duct (Atoufi et al. 2023); exchange through a convergent/divergent contraction (Cheung, 1990); and the arrested salt wedge (Yang et al. 2023). The dynamics of instability and mixing is subtly different in each case. The most effective mixing occurs in two-layer flow over topography downstream due to the combined action of Kelvin-Helmholyz billowing upstream of the jump and the jump itself.
Year: 2025