Parameters influencing dilute‐phase pneumatic conveying through pipe systems: A computational study by the Euler/Lagrange approach

Abstract

The present contribution summarizes research related to the numerical computation of pneumatic conveying systems applying the Euler/Lagrange approach. For that purpose, a rigorous modelling of the particulate phase was aspired, including the relevant fluid dynamic forces, particle-wall collisions with wall roughness and inter-particle collisions. For the validation of the computations, experiments of Huber and Sommerfeld were selected for the conveying through a 80 mm stainless steel pipe with 5 m horizontal pipe, bend and 5 m vertical pipe. The majority of the computations were done for the same pipe system; however, in this instance, consisting of 150 mm stainless steel pipes. In these cases the average conveying velocity was 27 m/s and the particle mass loading was 0.3 (mass flow rate of particles/mass flow rate of air). For this configuration the influence of wall roughness, inter-particle collisions, particle size, and mass loading on the resulting particle concentration distribution, the secondary flow as well as the pressure drop in the different pipe elements was analyzed. Moreover, a segregation parameter was defined which describes the location of the maximum particle concentration throughout the pipe system. The secondary flow intensity (SFI) was used to characterize the influence of the particle phase on the developing structure of the secondary flow.

Numerical investigation of mass loading effects on elbow erosion

“…Interestingly, this reduction in the particle-to-wall collisions is in contrary to the findings of Laín and Sommerfeld [38] and Sommerfeld and Laín [39], who investigated the gas-particle flow in a pneumatic conveying system. They showed that inter-particle collisions actually increase the number of particle-to-wall collisions in the bend.…”

“…7. Numerical and experimental penetration ratios versus bend curvature angle for one, two and four-way couplings and mass loading ϕ = 0.25. contrast with the observations of Laín and Sommerfeld [39], who found smooth contours for the particle concentration in a two-way calculation. Such a discontinuity is owing to the geometric characteristics of the bend we investigated.…”

Prediction of Two-Phase Heat Transfer and Pressure Drop in Dilute Gas–Solid Flows: A Numerical Investigation

“…The particle-particle collision and the particlewall collision play a significant role in gas-solid flows. [4,5] Several researchers [6][7][8][9][10][11] numerically studied the hydrodynamics of gas-solid flows. Recently, Patro and Dash [11] extensively studied the hydrodynamics and pressure drop characteristics in horizontal gas-solid flows using a two-fluid model.…”

Influence of inter‐particle collisions and agglomeration on cyclone performance and collection efficiency

“…In order to represent such a phenomenon, the implemented wall collision model accounting for wall roughness is based in the model described and validated by Sommerfeld and Huber . The wall roughness experienced by a particle is simulated assuming that the instantaneous impact angle is composed of the particle trajectory angle plus a stochastic contribution due to wall roughness, drawn from a normal distribution with a standard deviation Δγ, which depends on the structure of wall roughness and particle size . In the considered cases, regardless of particle size, the standard deviation of the roughness angle was assumed to be Δγ = 10°.…”

“…In the considered cases, regardless of particle size, the standard deviation of the roughness angle was assumed to be Δγ = 10°. This value was chosen based on the good agreement obtained for previous studies of pneumatic conveying in channels and pipes …”