DYNAMICS OF SATURATION OF A STRATUM IN THE ZONE OF PENETRATION OF A DRILLING AGENT INTO IT

A solution of the nonlinear problem on the driving of the oil from an oil-bearing stratum of fi nite length by the fi ltrate of a drilling agent (fl ushing water) has been constructed with the use of the asymptotic method. On the basis of this solution, the saturation fi eld of the stratum in the zone of penetration of the fl ushing water into it was investigated with regard for the process of opening of the stratum by drilling. The indicated solution defi nes the movement, along the thickness of the stratum, of the boundary, corresponding to the position of a drill bit, above which the saturation of the stratum with the fi ltrate of the fl ushing water and the velocity of fi ltering of this water are prescribed, and, below this boundary, the velocity of the water fi ltration fl ow and the stratum saturation are assumed to be equal to zero. It is shown that, within large times, the solution obtained conforms with the known Buckley–Leverett expression. On the basis of the computational experiments, spatial and time distributions of the stratum saturation in the zone of penetration of the fl ushing water into it have been constructed with regard for the process of opening of the stratum.
A solution of the nonlinear problem on the driving of the oil from an oil-bearing stratum of fi nite length by the fi ltrate of a drilling agent (fl ushing water) has been constructed with the use of the asymptotic method. On the basis of this solution, the saturation fi eld of the stratum in the zone of penetration of the fl ushing water into it was investigated with regard for the process of opening of the stratum by drilling. The indicated solution defi nes the movement, along the thickness of the stratum, of the boundary, corresponding to the position of a drill bit, above which the saturation of the stratum with the fi ltrate of the fl ushing water and the velocity of fi ltering of this water are prescribed, and, below this boundary, the velocity of the water fi ltration fl ow and the stratum saturation are assumed to be equal to zero. It is shown that, within large times, the solution obtained conforms with the known Buckley–Leverett expression. On the basis of the computational experiments, spatial and time distributions of the stratum saturation in the zone of penetration of the fl ushing water into it have been constructed with regard for the process of opening of the stratum.
Author:  A. I. Filippov, M. A. Zelenova, I. F. Kabirov, T. M. Levina
Keywords:  stratum, saturation, asymptotic method, fl ushing water, drilling
Page:  51