关键词: 四参数流变模式, 旋流器, 非牛顿流体, 速度场, 压力场, 数值模拟

Abstract: A four-parameter rheological model was used to describe the non-Newtonian flow characteristics of drilling fluid, combining with Reynolds stress model, the influence of non-Newtonian behavior on the flow field of hydrocyclone separation was examined, and the distributions of velocity and pressure fields of three kinds of fluid were obtained. The results showed that the flow field simulation results were in accordance with the previous experimental results, indicating that the simulation was were reliable. Their fluid flow field distributions were similar, but at the same position, the static pressure (4.02 and 3.77 MPa) and axial velocity (11.9 and 12.4 m/s) of non-Newtonian fluid were greater than those of Newtonian fluid water (3.22 MPa and 11.7 m/s), and the tangential velocity of non-Newtonian fluid (42.5 and 39.7 m/s) was less than that of Newtonian fluid water (47.5 m/s). Compared with power law fluid, the static pressure of four-parameter rheological fluid decreased from 4.02 to 3.77 MPa and the pressure drop from 4.79 to 4.51 MPa, the energy loss was reduced by 0.28 MPa, while the tangential velocity was decreased by 2.8 m/s and the envelope of zero vertical velocity was closer to the wall, which was not conducive to the separation of fluid media.

Key words: four-parameter rheological model, hydrocyclone, non-Newtonian fluid, velocity field, pressure field, numerical simulation