Liao Yon, Li Zhao-min
Oil Drilling & Production Technology
Foam fluid is widely used in sand-flushing operations in oilfields, while the prop-carrying capability of foam fluid is very important. Numerical simulation for prop-carrying capability of foam fluid is conducted using the discrete phase model of FLUENT. The sand carrying rate of sands with different diameters in concentric and eccentric annular spaces is obtained, impact of velocity and annular space eccentricity on prop-carrying capability of foam fluid is researched, and safe sand carrying conditions in sand-flushing operations for horizontal oil wells are obtained. The results show that sand carrying rate of sands with different diameters has different relations with the inclination angle of annular pipes. Sand carrying rate increases with the increase of foam fluid velocity, while it decreases because of annular space eccentricity. The impact of annular space eccentricity on the horizontal segment is less than that on the vertical segment of oil wells.