The influence of the blade thickness on the pressure pulsations in a ceramic centrifugal slurry pump with annular volute

Abstract

Due to the serious abrasion caused by the existence of solid phase in slurry, the slurry pumps usually adopt thick impeller blades to prolong its service life. In this paper, the influence of the blade thickness on the transient characteristics, the vibration, and the solid–liquid two-phase flow in a ceramic centrifugal pump with annular volute was investigated by the numerical method. And the experimental test was also conducted for computational fluid dynamics validation. The static pressure, the velocity, the force, and the solid fraction within the impeller passage and the volute casing have been discussed in detail. The results show that the influence of the blade thickness variation on the pressure fluctuation intensity is larger at the impeller inlet than that at the impeller exit and is larger at the pressure sides than that at the suction sides. The pressure fluctuation intensity decreases at the regions close to the volute tongue with the increase in the blade thickness. However, it increases at the regions, which are away from the volute tongue as the blade thickness increases. Moreover, the torque on the impeller, the radial force, and the axial force decreases with the increase in the blade thickness. Meanwhile, increasing the blade thickness will disperse the solid fraction at the impeller back shroud and make the regions with high solid fraction on pressure sides offset towards the impeller exit with a larger blade thickness, thus prolonging the service life of the impeller. However, the best efficiency point offsets to a low flow rate condition. The results are expected to pave the way for further optimization of impeller blade profile.