(Press-News.org)
The Vortex Particle Method (VPM), a meshless vortex flow simulation approach, is gaining traction for its efficient simulation of unsteady vortex wakes evolution that is shed by aircrafts, rotors and wind turbines. It outperforms traditional grid-based CFD methods with faster computation, lower dissipation, and easier satisfaction of the CFL stability condition. However, traditional VPM has huge challenge on accurately simulating these complex flows, due to its poor numerical stability, which is compromised by factors such as Lagrangian particle distortion, vorticity field divergence, and inadequate modeling of turbulent dissipation. These issues restrict its application in high Reynolds number and high velocity gradient flows.
Recently, a team of aviation researchers led by Min Chang from Northwestern Polytechnical University in China have developed a Stability-enhanced VPM (SEVPM) based on a Reformulated VPM (RVPM) constrained by conservation of angular momentum. SEVPM integrated a relaxation scheme to suppress the divergence of the vorticity field and coupled a Sub-Grid Scale (SGS) model to account for turbulence dissipation caused by vortex advection and vortex stretching. These advancements enable stable, high-fidelity simulations of complex flows that were previously computationally prohibitive.
The team published their work in the Chinese Journal of Aeronautics (Vol. 38, Issue 7, 2025).
The new SEVPM addresses these issues by incorporating a Reformulated VPM (RVPM) that enforces angular momentum conservation, a relaxation scheme to maintain a divergence-free vorticity field, and a novel Sub-Grid Scale (SGS) model that accounts for turbulence dissipation from both vortex advection and stretching. These advancements enable VPM more stable and precise simulations of complex fluid dynamics, providing engineers and researchers with a more reliable tool for predicting fluid behavior of vortex flow in practical applications.
The researchers demonstrated that their SEVPM can accurately and stably simulate high Reynolds number flows and shear turbulence. Through a series of validation cases, including isolated vortex ring evolution, leapfrogging vortex rings, and round turbulent jet simulations, they showed that the new method significantly improves numerical stability and accurately resolves fluctuating components and Reynolds stresses in turbulence. This advancement paves the way for more reliable and efficient computational simulations in fluid dynamics, which is essential for understanding and predicting complex flow phenomena in engineering applications. "Engineers hit a wall simulating shear turbulence like jet exhausts or rotor interactions with traditional VPM. Our work tears down that wall," says lead author Xiaoxuan Meng.
The researchers plan to further validate and refine the Stability-enhanced VPM by applying it to more complex and realistic flow scenarios. Future work includes simulating the aerodynamic interactions of multirotor systems, wake dynamics of wind turbines, and other practical applications in aeronautics and renewable energy. The ultimate goal is to establish the Stability-enhanced VPM as a robust computational tool for high-fidelity fluid flow simulations, enabling more accurate predictions and driving innovation in design and optimization of aerospace and energy systems. "Our ultimate goal is making high-fidelity turbulence simulation as routine as structural analysis," says Min Chang. "This unlocks smarter, greener aviation and energy systems."
Original Source
Xiaoxuan Meng, Junqiang Bai, Ziyi Xu, Min Chang, Zhe Hui. Stability-enhanced viscous vortex particle method in high Reynolds number flow and shear turbulence[J]. Chinese Journal of Aeronautics, 2025, 38(7): 103361, https://doi.org/10.1016/j.cja.2024.103361.
About Chinese Journal of Aeronautics
Chinese Journal of Aeronautics (CJA) is an open access, peer-reviewed international journal covering all aspects of aerospace engineering, monthly published by Elsevier. The Journal reports the scientific and technological achievements and frontiers in aeronautic engineering and astronautic engineering, in both theory and practice. CJA is indexed in SCI (IF = 5.7, Q1), EI, IAA, AJ, CSA, Scopus.
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(doi:10.1001/jama.2025.9855)
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