@article{Lai2025, 
author = {Zenan Lai and Deming Nie},
title = {Two-Dimensional Numerical Study on the Flow Past Two Staggered Cylinders in a Channel},
year = {2025},
journal = {Fluid Dynamics & Materials Processing},
volume = {21},
number = {9},
pages = {2131-2148},
keywords = {Lattice Boltzmann method, staggered cylinders, Strouhal number, drag coefficient},
url = {https://www.sciopen.com/article/10.32604/fdmp.2025.068091},
doi = {10.32604/fdmp.2025.068091},
abstract = {The lattice Boltzmann method (LBM) is employed to simulate flow around two staggered cylinders within a confined channel. The numerical model is validated against existing experimental data by comparing drag coefficients and Strouhal numbers in the single-cylinder configuration. The study systematically investigates the influence of vertical ( h) and horizontal ( l) spacing between the cylinders, as well as the Reynolds number ( Re = 0.1–160), on the hydrodynamic forces, streamline patterns, and vortex dynamics. Results indicate that reducing the horizontal spacing  l suppresses flow separation behind the upstream cylinder, while either excessively small or large vertical spacing  h diminishes separation in the downstream cylinder. The onset of periodic vortex shedding is delayed due to inter-cylinder interactions, with the critical Reynolds number increasing to  Rec = 71–112, significantly higher than that of a single-cylinder case ( Rec ≈ 69). During the vortex shedding regime, the downstream cylinder exhibits a greater lift force fluctuation compared to the upstream cylinder. At  Re = 160, the root-mean-square lift coefficient ( CL′) ranges from approximately 0.17 to 0.56 for the downstream cylinder, and from 0.018 to 0.4 for the upstream one. The shedding frequency, characterized by the Strouhal number ( St), increases with Reynolds number, reaching  St = 0.12–0.18 at  Re = 160. Variations in  h and  l significantly influence  St, with a decrease in  l or an increase in  h lowering the shedding frequency—this effect is more pronounced in the horizontal direction.}
}