Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.jconhyd.2005.08.001
Title (Primary) 3-D numerical evaluation of density effects on tracer tests
Author Beinhorn, M.; Dietrich, P. ORCID logo ; Kolditz, O. ORCID logo
Source Titel Journal of Contaminant Hydrology
Year 2005
Department ENVINF; MET
Volume 81
Issue 1-4
Page From 89
Page To 105
Language englisch
Keywords Tracer test; Density-dependent flow; Electrical methods; Groundwater; Model; Heterogeneity
Abstract In this paper we present numerical simulations carried out to assess the importance of density-dependent flow on tracer plume development. The scenario considered in the study is characterized by a short-term tracer injection phase into a fully penetrating well and a natural hydraulic gradient. The scenario is thought to be typical for tracer tests conducted in the field. Using a reference case as a starting point, different model parameters were changed in order to determine their importance to density effects. The study is based on a three-dimensional model domain. Results were interpreted using concentration contours and a first moment analysis. Tracer injections of 0.036 kg per meter of saturated aquifer thickness do not cause significant density effects assuming hydraulic gradients of at least 0.1%. Higher tracer input masses, as used for geoelectrical investigations, may lead to buoyancy-induced flow in the early phase of a tracer test which in turn impacts further plume development. This also holds true for shallow aquifers. Results of simulations with different tracer injection rates and durations imply that the tracer input scenario has a negligible effect on density flow. Employing model cases with different realizations of a log conductivity random field, it could be shown that small variations of hydraulic conductivity in the vicinity of the tracer injection well have a major control on the local tracer distribution but do not mask effects of buoyancy-induced flow.
Persistent UFZ Identifier
Beinhorn, M., Dietrich, P., Kolditz, O. (2005):
3-D numerical evaluation of density effects on tracer tests
J. Contam. Hydrol. 81 (1-4), 89 - 105 10.1016/j.jconhyd.2005.08.001