Abstract
Gas-solid two-phase flow in a 90? bend has been studied numerically. The bend geometry is squared cross section of (0.15 m × 0.15 m) and has a turning radius of 1.5 times the duct's hydraulic diameter. The solid phase consists of glass spheres having mean diameter of 77 µm and the spheres are simulated with an air flowing at bulk velocity of 10 m/s. A computational fluid dynamic code (CFX-TASCflow) has been adopted for the simulation of the flow field inside the piping and for the simulation of the particle trajectories. Simulation was performed using Lagrangian particle-tracking model, taking into account one-way coupling, combined with a particle-wall collision model. Turbulence was predicted using k-ε model, wherein additional transport equations are solved to account for the combined gas-particle interactions and turbulence kinetic energy of the particle phase turbulence. The computational results are compared with the experimental data present in the literature and they were found to yield good agreement with the measured values.
Highlights
Bends are a common element in any piping system of gas-solid flow applications such as pneumatic conveyers, pneumatic dryers, chemical industries and food processing
Yang and Kuan [1] and Kuan [2] performed a CFD predictions of dilute gassolid flow through a curved 90 ̊ duct bend based on a Differential Reynolds Stress Model (DRSM) for calculating turbulent flow quantities and a Lagrangian particle tracking model for predicting solid velocities
They employed the modified Eulerian-Eulerian two fluid model to predict the gas-particle flows and studied a dilute gas-particle flows over a square sectioned 90 ̊ bend employing two approaches to predict the gas-particle flows, namely the Lagrangian particle tracking model and Eulerian two fluid model
Summary
Bends are a common element in any piping system of gas-solid flow applications such as pneumatic conveyers, pneumatic dryers, chemical industries and food processing. Yang and Kuan [1] and Kuan [2] performed a CFD predictions of dilute gassolid flow through a curved 90 ̊ duct bend based on a Differential Reynolds Stress Model (DRSM) for calculating turbulent flow quantities and a Lagrangian particle tracking model for predicting solid velocities They found that the more complex DRSM failed to predict the pressure gradient effects that prevail within the bend; the predicted turbulence intensity only bears qualitative resemblance to the measured distribution. The computational results are compared with the LDV results of Kliafas and Holt [6] and were found to yield good agreement with the measured values and the Eulerian model provided useful insights into the particle concentration and turbulence behavior, they found that both Eularian-Eularian and Eularian-Lagrangian approaches provided reasonably good comparison for gas and particle velocities together with the fluctuation for the gas phase They stated that despite the fact that the particle fluctuation using the Eularian model showed good comparison with the experimental data. Ibrahim et al [7] studied numerically the behavior of gas-solid flow in 90 ̊
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
