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Updated: Jan 10, 2026
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Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
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Classically studied coherent structures only paint a partial picture of wall-bounded turbulence
Andrés Cremades1,2, Sergio Hoyas3, Ricardo Vinuesa4,5
1Instituto Universitario de Matemática Pura y Aplicada, Universitat Politécnica de Valéncia, Valencia, Spain. andrescb@kth.se.
Nature Communications
|November 19, 2025
Summary
Understanding turbulent flow energy transfer remains a challenge. This study introduces a data-driven method using deep learning and SHAP values to objectively identify crucial flow regions, advancing turbulent flow analysis.
Area of Science:
- Fluid Dynamics
- Turbulence Research
- Computational Science
Background:
- The mechanisms of energy transport and dissipation in turbulent flow are not fully understood after 140 years of research.
- Previous studies focused on coherent structures, but their precise role in flow development remains uncertain.
Purpose of the Study:
- To develop a data-driven methodology for objectively identifying high-importance regions in turbulent flows.
- To compare these data-identified regions with classical coherent structures.
Main Methods:
- A deep-learning model was trained to predict the future state of the turbulent flow.
- The gradient SHAP (SHapley Additive exPlanations) algorithm was employed to quantify the importance of each grid point.
- High-importance regions were computed using SHAP values.
Main Results:
- The SHAP analysis objectively identified regions of higher importance within the turbulent flow.
- These identified regions showed varying degrees of agreement with traditional coherent structures.
- No complete correlation was found between SHAP-identified regions and any single type of classical structure.
Conclusions:
- The proposed SHAP-based methodology offers an objective approach to pinpoint critical areas in turbulent flows.
- This method provides a new perspective on the relationship between flow structures and energy dynamics.
- The findings suggest a more nuanced understanding of turbulent flow organization beyond classical coherent structures.
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