Research on hydraulic characteristics’ sensitivity analysis of the hydraulic inclined shaft turning

Abstract

Abstract The parameters of the hydraulic inclined shaft turning directly affects the flow field characteristics in the bending section and the construction difficulty of the bending section. Three-dimensional computational fluid dynamics (CFD) numerical simulation method was used to systematically study the hydraulic characteristics under different flow velocities, turning radii and turning angles. The results indicate that the flow velocities and the size of the turning radius have little influence on the flow velocity distribution in the bending section. The larger the turning angle, the larger the fast flow velocity area in the bending section. But the extreme values of fast flow velocity remain basically unchanged, and the length required for adjusting the flow velocity distribution after the curved section becomes longer. The faster the flow velocity, the smaller the turning radius, and the larger the turning angle, the greater the centrifugal force generated and the more pronounced the difference in pressure distribution between the inside and outside of the bend section. The head loss in the bending section is consistent with the empirical formula in the specifications. As the radius of curvature gradually increases from 1D to 3D, the head loss (primarily due to local head loss) decreases gradually. When the radius of the bending section continues to increase, the reduction in local head loss becomes less significant, but the increase in frictional head loss leads to a slight overall increase in head loss.