Laminar bottom gravity currents: friction factor-Reynolds number relationship

作者：Yilmaz Nazli A; Testik Firat Y^*; Chowdhury Mijanur R

来源：Journal of Hydraulic Research, 2014, 52(4): 545-558.

DOI：10.1080/00221686.2013.878402

• Fanning friction factor
• fluid-mud gravity currents
• laminar flows
• non-Newtonian fluid flows
• power-law fluids

This study elucidates a relationship between the Fanning friction factor and the Reynolds number for the laminar propagation of constant-flux gravity currents. The particular motivation for this study was related to the pipeline disposal of dredged fluid-mud where non-Newtonian bottom gravity currents form. The power-law rheology model, which has been shown to model fluid-mud rheology well, was incorporated in the theoretical analysis. The proposed Fanning friction factor-Reynolds number relationship includes a proportionality constant (henceforth, the shape factor) that considers the shape of the current. For non-Newtonian fluid-mud gravity currents, a relationship for the shape factor was developed through laboratory experiments. Different potential applications of the developed friction factor-Reynolds number relationship are discussed. In this regard, a new viscous propagation model was developed and evaluated through comparisons with laboratory experimental data for fluid-mud gravity currents. The approach presented in this manuscript can be extended for currents of different fluids propagating over smooth and rough bottoms.

• 出版日期2014