Javaux, Mathieu
[UCL]
Vanclooster, Marnik
[UCL]
Within this presentation, the influence of the flow rate and scale on the transport of a non-reactive saline tracer in a large undisturbed sandy subsoil monolith is stud- ied. The monolithique sample was extracted in a quarry at 10 m depth from the sur- face and equipped in the laboratory with tensiometers, temperature probes and time- domain-reflectometry probes. Eight solute breakthrough experiments were conducted at different flow rates allowing to elucidate the solute transport parameters in terms of a variable flow rate. The latter was controlled by means of a high precision irri- gation system in a range between 1 and 100 cm/d. Solute resident concentrations of a saline tracer was continuously monitored through 10 TDR probes of 0.4 m length, inserted in 3 vertical transects. Time series were used to estimate apparent dispersiv- ities and velocities at different locations by inversion of the analytical solution of the convection-dispersion equation for solute resident concentrations. The evolution of the apparent dispersivity with depth is studied in order to characterize the transport pro- cesses. Horizontal heterogeneity of the effective parameters is related to a mesoscale effective dispersivity factor. Furthermore, influence of the flow rate on the estimated dispersivity is also investigated.
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Bibliographic reference |
Javaux, Mathieu ; Vanclooster, Marnik. Experimental determination of the space and flow rate dependency of the subsoil transport parameters.EGS-General Assembly (Nice, April). In: Book of abstracts, 2002, p. EGS02-A-03652 |
Permanent URL |
http://hdl.handle.net/2078.1/84044 |