The Lifting Efficiency of Coarse Particles in Vertical Pipes
A numerical method has been developed to analyze the solid-liquid two-phase flow with coarse particles in vertical pipes. Based on the numerical study, a concept of lifting efficiency has been suggested to describe the efficiency of lifting solid particles by the moving liquid. The lifting efficiency can be defined as, where vs is the average velocity of the solid particles and vl is the average speed of the liquid. It was found that when the liquid speed is lower than 3m/s, the lifting efficiency is increased when the liquid speed is increased. On the other hand if the liquid speed is more than 3m/s, the lifting efficiency will decrease if the liquid speed increases. It was also found that the speed of the particles will decrease if pipe vibration frequency is increased. However the lifting efficiency remains unchanged compared with the stationary pipes.
H. C. Pan et al., "The Lifting Efficiency of Coarse Particles in Vertical Pipes", Applied Mechanics and Materials, Vols. 66-68, pp. 1219-1224, 2011