Influence of a channel bend on the purging of saline fluid from a cavity by an overflow of fresh water

Abstract

A numerical and laboratory investigation on the purging of saline fluid from a cavity within a $60^\circ$~channel bend is presented to characterise the purging process in open channel bends. The numerical simulation uses a three dimensional, direct numerical simulation, fractional-step solver. The geometry replicates the laboratory experiment to define the mixing processes of a cavity with vertical sidewalls occupying the centre~$20^\circ$ of the $60^\circ$~channel bend. The secondary circulation as the flow moves through the bend increases the vertical momentum exchange within the cavity and hence destabilises the saline interface. References

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