000125694 001__ 125694
000125694 005__ 20190316234313.0
000125694 037__ $$aPROC
000125694 245__ $$aViscoplastic flows
000125694 269__ $$a2006
000125694 260__ $$bAGU$$c2006$$aSan Francisco
000125694 336__ $$aConference Proceedings
000125694 490__ $$aEos Trans. AGU$$v87(52)
000125694 520__ $$aActually little is known on the physical processes involved in avalanches or debris flows. We tackle this difficult issue by carrying out idealized experiments, where we focus on the motion of highly time-dependent flows of non-Newtonian fluids. The objective is to test various propositions of governing equations experimentally and numerically. Experiments involve unleashing a finite volume of fluid down an inclined plane. For now, we use a simple viscoplastic material (viscoplastic gel called Carbopol), whose physical properties approach those of natural materials very roughly. The motion of the surge can be tracked using image processing techniques: we project fringes onto the free surface, which are deformed as a resulting of the bulk motion. Relating deformation and flow depth makes it possible to obtain a three-dimensional map of the surge. In parallel, we extend a three-dimensional Navier-Stokes solver to numerically model the surge motion. The material considered in the simulations is a Herschel-Bulkley fluid. In order to compare the numerical results with our experimental data, we use the rheological parameters of the Carbopol gel, which were obtained independently using a rheometer. The key problem in these numerical simulations is the treatment of the yield stress as well as the boundary conditions at the front (contact line). In this talk, we present our preliminary results on the flow structure within the leading edge.
000125694 6531_ $$aViscoplastic flow
000125694 7112_ $$dDecember 11-15$$cSan Francisco$$aAGU Fall Meeting
000125694 720_1 $$aRentschler, M.$$eed.$$g169272$$0240367
000125694 720_1 $$aCochard, S.$$eed.$$g100875$$0240368
000125694 720_1 $$aAncey, C.$$eed.$$g148669$$0240366
000125694 8564_ $$uhttp://www.agu.org/meetings/fm06/?content=program$$zURL
000125694 909C0 $$xU10257$$0252029$$pLHE
000125694 909CO $$qGLOBAL_SET$$pproc$$ooai:infoscience.tind.io:125694$$pENAC
000125694 937__ $$aLHE-PROC-2008-003
000125694 973__ $$sPUBLISHED$$aEPFL
000125694 980__ $$aPROC