Speaker: Miguel Moyers, Applied Mathematics at University British Columbia
Title:
Date: Thursday, January 13, 2005
Time: 2:30 - 3:20pm
Place: Guggenheim Room 408d
Abstract: A two-dimensional evolution model for displacement flows occurring in the primary cementing of an oil well is derived. The geometry is a long narrow eccentric annulus, between the casing and the well rock wall.
The model consists of solving a diffusion-advection equation for the fluids concentrations and a quasilinear parabolic-type equation for the stream function. Coupling is through the velocity field and the concentration-dependent fluid properties.
The effects of increasing eccentricity are those of unstable displacements. Long fingers and narrow-side mud channels may form. The aim of the work we present is the study of interfacial instabilities when long fingers develop. Treating the displacement as a parallel flow and using normal modes analysis, we show that for changes in the properties of the fluids linear instabilities at the interface sometimes occur.
Everyone welcome!