Reynolds number dependence of particle transport in a 90° bend with electrostatic effects--颗粒学报PARTICUOLOGY

Yan, Y., Zhao, Y., Liu, M., & Yao, J. (2023). Reynolds number dependence of particle transport in a 90° bend with electrostatic effects. Particuology, 77, 91-104. https://doi.org/10.1016/j.partic.2022.08.015

Reynolds number dependence of particle transport in a 90° bend with electrostatic effects

Yudong Yan, Yanlin Zhao ^*, Min Liu, Jun Yao

International Joint Laboratory on Clean Energy Science and Technology, Beijing Key Laboratory of Process Fluid Filtration and Separation, College of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing, 102249, China

10.1016/j.partic.2022.08.015

Volume 77, June 2023, Pages 91-104

Received 20 April 2022, Revised 9 August 2022, Accepted 24 August 2022, Available online 13 September 2022, Version of Record 2 December 2022.

E-mail: ylzhao@cup.edu.cn

Highlights

• Particle transport in a 90° bend flow under the effect of electrostatics is simulated.

• Three flow Reynolds numbers, 34000, 40000 and 58000, are considered.

• The electrostatic field is asymmetric in the vertical direction and radial direction.

• Particle accumulation near the wall increases with electrostatics.

• The plume pattern of particle distribution disappeared due to electrostatics.

Abstract

In this work, particle transport in a fully developed turbulent 90° bend flow at the “electrostatic equilibrium” state is simulated using large eddy simulation coupled with Lagrangian particle tracking technique. The flow Reynolds numbers (based on bulk velocity) considered is from 34000 to 58000. Three particle size 5, 10 and 50 μm are considered and their corresponding St number are from 2.2 to 547. Simulation results of the bend flow agree well with experimental data. The electrostatic field formed in the bend is symmetric in the spanwise direction but asymmetric in the vertical direction and radial direction, which is independent of Reynolds number. The minimum electrostatic field strength occurs at r/r_a = 0.25 near the inner wall of the bend. Particles transported in a bend gradually accumulate near the wall due to turbophoresis, such trend is improved by electrostatics. In addition, under the effect of electrostatics, the plume pattern of particle distribution disappeared. Particle concentration at the inner wall of the bend is higher than that at the outer wall, which depends on the combined effect of electrostatics and Dean vortices in the bend.

Graphical abstract

Keywords

Electrostatics; Bend; Turbulent flow; Particle transport; Large eddy simulation

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