| description abstract | Particles deposition and plug-in wellbore cause lots of damage and efficiency reduction during oil and gas exploitation. Transportation has been a focus for safety and production improvement. The annular flow field and particles transport behavior have been investigated using computational fluid dynamics with an renormalization group k–ɛ method. Effects of particles volume concentration, washing fluid concentration with power-law shearing, annular eccentricity, flow rate, and rotation speed have been researched to get the mechanism of particles accumulation and transport behavior. The results show that an increase in eccentricity causes velocity reduction of the annular narrow gap area, particles easily deposit, accumulate, and are hard to transport; increasing flow rate and fluid concentration apparently improve particles transportation and reduce deposition, pressure loss increases; inlet particles volume concentration increases deposition starting position and deposition length, the inner pipe rotation facilitates particles’ second suspension. | |
