Particle Flow within the Pulsed Liquid-Solid Fluidized Bed

Hydraulic transport with reciprocating positive displacement pumps offers great opportunities to transport tons of particulate solids over large distances. Using the pressure rigid operating principle provides very high pressure, yet predicting the impact of the unsteady drive kinematics on flow fields and particle motion is challenging. Few is known about the physical interaction at phase boundaries for liquid-solid flows against gravity on microscopic levels. Especially lack of knowledge under accelerated flow condition make it difficult to estimate the transport efficiency and reliability of new pump plants. In order to mimic the liquid-solid particulate system under pulsed flow condition, an experimental fine-tunable flow setup with a well-defined fluidized bed has been established. An acquiring method based on simultaneously flow measurement and imaging techniques for gathering extensive, time-resolved data of particle motion and flow has been developed and applied for different input parameters. First evaluation approaches have been suggested and applied to each parameter set in order to elaborate potential usage and limitations. Results of the parameter study gave first impressions about how pulse duration, flow amplitude and solid volume fraction affect particle motion. While deep knowledge of particle motion and movement patterns can be directly obtained from the image data, valuable correlations could be found between detailed particle motion and macroscopic bed parameters such as bed height and pressure loss.