|Table of Contents|

Review on application of CFD-DEM coupling method in study of local scouring around bridge piers(PDF)

长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]

Issue:
2026年2期
Page:
85-105
Research Field:
桥梁与隧道工程
Publishing date:

Info

Title:
Review on application of CFD-DEM coupling method in study of local scouring around bridge piers
Author(s):
QI Hong-liang1; 2;  YU Ying-tao1;  TIAN Wei-ping1;  LI Jia-chun1;  YAN Xi1;  WANG Han-yu1
(1. Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang'an University,Xi'an 710064, Shaanxi, China; 2. Xi'an Key Laboratory of Geotechnical Engineering for Green and Intelligent Transport, Chang'an University, Xi'an 710064, Shaanxi, China)
Keywords:
bridge engineering;  local scouring;  CFD-DEM;  coupling method;  macroscopic and microscopic mechanisms
PACS:
U441.2
DOI:
10.19721/j.cnki.1671-8879.2026.02.007
Abstract:
The recent advances in the application of coupled computational fluid dynamics-discrete element method(CFD-DEM)for studying the local scouring around bridge piers were systematically reviewed. The focuses were on the dynamical mechanism of local scouring around bridge piers, the technical evolution of CFD-DEM coupling method, and their corresponding coupling strategies. The application of CFD-DEM coupling method in local scouring around bridge piers was analyzed from both the macroscopic and microscopic perspectives. On this basis, the current limitations in this research field were identified. The research results indicate that the CFD-DEM coupling method can effectively demonstrate the evolution process of bridge pier bypass flow, horseshoe, wake vortices and the relationship between initiation, transport and deposition of sediment particles, thereby providing an analytical tool from macroscopic to mesoscopic levels for revealing the local scouring mechanisms. Existing studies propel the transition of bridge local scouring research from scour depth prediction to particle dynamics process analysis. However, the simulation accuracy of turbulent structures under high Reynolds number conditions remains limited. Long-term computation at full-bridge scale poses significant challenges. Furthermore, the spherical particle assumption in DEM deviates from the morphology of natural sediment. The modeling of non-spherical particles still requires a trade-off between accuracy and efficiency. The computational cost of CFD-DEM coupling is relatively high. Although the coarse-graining method can improve efficiency, it may weaken the representations of local flow field and mesoscopic particle interaction. Additionally, the data exchange, time-step coordination and numerical stability of current multi-software coupling frameworks require further improvement. Future research should prioritize enhancing the parallel computing efficiency, refining the non-spherical sediment particle dynamics model, developing high-fidelity coarse-graining methods, and promoting the integration of coupling architectures alongside the in-depth application of AI-aided simulation.1 tab, 22 figs, 90 refs.

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