Author(s): Yukie Tanino; Heidi M. Nepf
Linked Author(s): Heidi M. Nepf
Keywords: Dispersion; Turbulence; Aquatic vegetation
Abstract: Laser-induced fluorescence was used to measure the lateral dispersion of passive solute in random arrays of rigid emergent cylinders with solid volume fraction ranging from φ = 0. 010 to 0. 35. These solid volume fraction correspond to those observed in aquatic plant canopies. Individual filaments of tracer were observed at a pore Reynolds number of Res ≡ Ups/ν 250. At low φ, Kyy / (Upd) rapidly increased with φ until Kyy / (Upd) = 0. 24 ± 0. 01. From φ = 0. 031 to 0. 20, Kyy / (Upd) decreased with φ until Kyy / (Upd) = 0. 13 ± 0. 01, and at φ = 0. 20, Kyy / (Upd) began to increase again. Existing models by Nepf (1999) (0 < φ ≤ 0. 031) and dense (φ ≥ 0. 20) arrays, respectively, but deviate outside this region. and Koch and Brady (1986) correctly describe the qualitative trends observed in sparse
Year: 2007