TY - JOUR
T1 - Effects of roughness and permeability on solute transfer at the sediment water interface
AU - Han, Xu
AU - Fang, Hongwei
AU - He, Guojian
AU - Reible, Danny
N1 - Publisher Copyright:
© 2017 Elsevier Ltd
PY - 2018/2/1
Y1 - 2018/2/1
N2 - Understanding the mechanisms of solute transfer across the sediment-water interface plays a crucial role in water quality prediction and management. In this study, different arranged particles are used to form typical rough and permeable beds. Large Eddy Simulation (LES) is used to model the solute transfer from the overlying water to sediment beds. Three rough wall turbulence regimes, i.e., smooth, transitional and rough regime, are separately considered and the effects of bed roughness on solute transfer are quantitatively analyzed. Results show that the classic laws related to Schmidt numbers can well reflect the solute transfer under the smooth regime with small roughness Reynolds numbers. Under the transitional regime, the solute transfer coefficient (KL+) is enhanced and the effect of Schmidt number is weakened by increasing roughness Reynolds number. Under the rough regime, the solute transfer is suppressed by the transition layer (Brinkman layer) and controlled by the bed permeability. Moreover, it is found that water depth, friction velocity and bed permeability can be used to estimate the solute transfer velocity (KL) under the completely rough regime.
AB - Understanding the mechanisms of solute transfer across the sediment-water interface plays a crucial role in water quality prediction and management. In this study, different arranged particles are used to form typical rough and permeable beds. Large Eddy Simulation (LES) is used to model the solute transfer from the overlying water to sediment beds. Three rough wall turbulence regimes, i.e., smooth, transitional and rough regime, are separately considered and the effects of bed roughness on solute transfer are quantitatively analyzed. Results show that the classic laws related to Schmidt numbers can well reflect the solute transfer under the smooth regime with small roughness Reynolds numbers. Under the transitional regime, the solute transfer coefficient (KL+) is enhanced and the effect of Schmidt number is weakened by increasing roughness Reynolds number. Under the rough regime, the solute transfer is suppressed by the transition layer (Brinkman layer) and controlled by the bed permeability. Moreover, it is found that water depth, friction velocity and bed permeability can be used to estimate the solute transfer velocity (KL) under the completely rough regime.
KW - Bed roughness
KW - Large Eddy Simulation
KW - Mass transfer coefficient
KW - Permeable bed
KW - Sediment water interface
UR - http://www.scopus.com/inward/record.url?scp=85032893265&partnerID=8YFLogxK
U2 - 10.1016/j.watres.2017.10.049
DO - 10.1016/j.watres.2017.10.049
M3 - Article
C2 - 29128680
AN - SCOPUS:85032893265
SN - 0043-1354
VL - 129
SP - 39
EP - 50
JO - Water Research
JF - Water Research
ER -