Stefan Wirtz Vom Fachbereich VI (Geographie/Geowissenschaften ...

Experimentelle Rinnenerosionsforschung vs. Modellkonzepte – Quantifizierung der hydraulischen und erosiven Wirksamkeit von Rinnen
The first run of RE 2 leads to a total runoff of 20 l, thus representing a proportion of 27.78 %,
at the end of the rill. The runoff peak reaches 0.066 l s -1 , 44% of the inflow intensity. During
the second run, 49.23 l reach the gauge at 25 m, indicating a runoff rate of 68.38%. Also the
runoff intensity is higher than in the other experiments, the maximum value reaches 0.102 l s -1
(68% of the inflow intensity). In the first run the runoff lasts for 812 s and starts 128 s after
the water input is stopped, in the second run, 66 s before stopping the discharge, the runoff
duration of 1198 s starts. The r-l-factor is 6.94 for the first run and 17.09 for the second run.
(Fig. 7b)
In RE 3A the water did not reach the measuring point after 15 m. In the second run (RE 3B)
10.09 l (14.01%) reached the measuring point with a maximum intensity of 0.052 l s -1 (34%
of the inflow intensity). The runoff starts 38 s before the pump is stopped and goes on for 354
s The r-l-factor is calculated here with 2.1.
Table 4: Overview over the flow velocities of the rill experiments: n.D.= no data
rill 1 rill 2 rill 3
Factor 1a 1b 2a 2b 3a 3b
MEAN water front [m s -1 ] 0.05 0.04 0.05 0.07 0.02 0.03
MEAN Tracer 1 [m s -1 ] 0.1 0.11 0.09 0.1 0.06 0.07
MEAN Tracer 2 [m s -1 ] 0.1 0.1 0.17 0.13 0.05 0.08
MAX waterfront [m s -1 ] 0.12 n.D. 0.13 0.11 0.04 0.06
MAX Tracer 1 [m s -1 ] 0.23 0.24 0.52 0.38 0.25 0.27
MAX Tracer 2 [m s -1 ] 0.2 0.24 1.35 1.09 0.11 0.28
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