@article{fdi:010053578,
  title = {{C}omparison of roughness models to simulate overland flow and tracer transport experiments under simulated rainfall at plot scale},
  author = {{M}ugler, {C}. and {P}lanchon, {O}livier and {P}atin, {J}. and {W}eill, {S}. and {S}ilvera, {N}orbert and {R}ichard, {P}. and {M}ouche, {E}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {S}aint-{V}enant equations have consistently proved capable of accurately simulating hydrographs at plot scale. {H}owever, recent works showed that even though the hydrograph is satisfyingly reproduced, the flow velocity field within the plot might be wrong, with the highest velocity largely underestimated. {M}oreover, the choice of roughness models to be used in the {S}aint-{V}enant equations is most often done in the purpose of increasing the hydrograph quality, while the actual travel time of water is ignored. {T}his paper presents a tracer experiment made on a 10-m by 4-m rainfall simulation plot, where travel time and tracer mass recovery as well as local flow velocity have been measured. {F}our roughness models are tested: (i) {D}arcy-{W}eisbach's model, (ii) {L}awrence's model, (iii) {M}anning's model with a constant roughness coefficient, and (iv) {M}anning's model with a variable roughness coefficient which decreases as a power law of the runoff water depth. {M}odels with a constant friction factor largely underestimate high velocities. {M}oreover, they are not able to simulate tracer travel-times. {L}awrence's model correctly simulates low and high velocities as well as tracer breakthrough curves. {H}owever, a specific set of parameters are required for each breakthrough curve from the same experiment. {T}he best results are obtained with the {M}anning's model with a water-depth dependent roughness coefficient: simulated velocities are consistent with measurements, and a single set of parameters captures the entire set of breakthrough curves, as well as tracer mass recovery. {T}he study reported here brings the following findings: (i) roughness coefficient is flow-dependent, (ii) faithful simulation of the velocity fields does not imply a good prediction of travel time and mass recovery, (iii) the best model is a {M}anning type model with a roughness coefficient which decreases as a power law of water depth. {T}he full dataset used in this work is available on request. {I}t can be used as benchmark for overland flow and transport models.},
  keywords = {{R}ainfall-simulation ; {T}racer injection ; {R}oughness model ; {F}riction law},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {402},
  numero = {1-2},
  pages = {25--40},
  ISSN = {0022-1694},
  year = {2011},
  DOI = {10.1016/j.jhydrol.2011.02.032},
  URL = {https://www.documentation.ird.fr/hor/fdi:010053578},
}