English
Related papers

Related papers: Detection of dominant large-scale coherent structu…

200 papers

We study numerically a succession of transitions in pipe Poiseuille flow that leads from simple travelling waves to waves with chaotic time-dependence. The waves at the origin of the bifurcation cascade possess a shift-reflect symmetry and…

Fluid Dynamics · Physics 2012-12-04 Fernando Mellibovsky , Bruno Eckhardt

Extracting coherent patterns is one of the standard approaches towards understanding spatio-temporal data. Dynamic mode decomposition (DMD) is a powerful tool for extracting coherent patterns, but the original DMD and most of its variants…

Machine Learning · Computer Science 2021-02-22 Naoya Takeishi , Keisuke Fujii , Koh Takeuchi , Yoshinobu Kawahara

By using direct numerical simulations (DNS) at unprecedented resolution we study turbulence under rotation in the presence of simultaneous direct and inverse cascades. The accumulation of energy at large scale leads to the formation of…

Studying and interpreting the different flow patterns present in urban areas is becoming essential since they help develop new approaches to fight climate change through an improved understanding of the dynamics of the pollutants in urban…

Modal instabilities in a flow through a channel at high Reynolds and Mach numbers are studied for three-dimensional perturbations. In addition to the Tollmien-Schlichting modes, there exist higher modes in a channel flow that do not have a…

Fluid Dynamics · Physics 2022-08-03 M. Deka , G. Tomar , V. Kumaran

We present experiments on oscillating hydrofoils undergoing combined heaving and pitching motions, paying particular attention to connections between propulsive efficiency and coherent wake features extracted using modal analysis.…

Fluid Dynamics · Physics 2024-06-05 Morgan R. Jones , Mitul Luhar , Eva Kanso

Structural damage detection using non-contact sensing remains a challenging problem in structural health monitoring. This study presents a data-driven framework based on Dynamic Mode Decomposition (DMD) for extracting structural dynamics…

Systems and Control · Electrical Eng. & Systems 2026-05-05 R K B M Rizmi , Shabbir Ahmed

Experiments have been conducted to assess the sizes and energy fractions of structure in fully developed turbulent pipe flow regime in two pipe facilities, ColaPipe at BTU Cottbus-Senftenberg, and CICLoPE at University of Bologna, for shear…

Fluid Dynamics · Physics 2019-03-04 E. -S. Zanoun , Emir Öngüner , C. Egbers , G. Bellani , A. Talamelli

The presence of two-dimensional coherent structures in the near-field of the round jet has been established by several experimental investigations and direct Navier-Stokes simulations (DNS). Their study has a great importance to improve the…

Fluid Dynamics · Physics 2024-06-19 Philippe Reynier , Hieu Ha Minh

We consider a phase-separating mixture of active and passive fluids and explore morphological asymmetries of the emerging dominantly bicontinous dynamic emulsion. Two-dimensional numerical simulations reveal that the geometric and…

Soft Condensed Matter · Physics 2026-01-22 Rainer Backofen , Axel Voigt

Large scale coherent streaks are artificially forced in a well developed turbulent boundary layer at $\Redstar \approx 1000$ using an array of cylindrical roughness elements. Measures of the velocity field with particle image velocimetry…

Fluid Dynamics · Physics 2010-04-27 Pujals Gregory , Cossu Carlo , Depardon Sebastien

An inverse turbulent cascade in a periodic square box produces a coherent system-sized vortex dipole. We study the statistics of its motion by carrying out direct numerical simulations performed for various bottom friction $\alpha$, pumping…

Fluid Dynamics · Physics 2024-01-25 Vladimir Parfenyev

Dynamic Mode Decomposition (DMD) is an unsupervised machine learning method that has attracted considerable attention in recent years owing to its equation-free structure, ability to easily identify coherent spatio-temporal structures in…

Machine Learning · Computer Science 2022-02-16 Alex Viguerie , Gabriel F. Barros , Malú Grave , Alessandro Reali , Alvaro L. G. A. Coutinho

Spiral waves are ubiquitous spatiotemporal patterns that occur in various excitable systems. In cardiac tissue, the formation of these spiral waves is associated with life-threatening arrhythmias, and, therefore, it is important to study…

Biological Physics · Physics 2023-08-09 Mahesh Kumar Mulimani , Soling Zimik , Jaya Kumar Alageshan , Rahul Pandit

We present a novel reduced-order fluid simulation technique leveraging Dynamic Mode Decomposition (DMD) to achieve fast, memory-efficient, and user-controllable subspace simulation. We demonstrate that our approach combines the strengths of…

Magnetic reconnection is a fundamental mechanism of driving eruptive phenomena of different scales and may be coupled with turbulence as suggested by recent remote-sensing and in-situ observations. However, the specific physics behind the…

Solar and Stellar Astrophysics · Physics 2025-04-08 Yulei Wang , Xin Cheng , Mingde Ding

High-fidelity large-eddy simulations are suitable to obtain insight into the complex flow dynamics in extended wind farms. In order to better understand these flow dynamics, we use dynamic mode decomposition (DMD) to analyze and reconstruct…

Fluid Dynamics · Physics 2022-04-26 Xuan Dai , Da Xu , Mengqi Zhang , Richard J. A. M. Stevens

This article discusses the description of wall-bounded turbulence as a deterministic high-dimensional dynamical system of interacting coherent structures, defined as eddies with enough internal dynamics to behave relatively autonomously…

Fluid Dynamics · Physics 2018-03-20 Javier Jimenez

Detecting changes in data streams is a vital task in many applications. There is increasing interest in changepoint detection in the online setting, to enable real-time monitoring and support prompt responses and informed decision-making.…

Methodology · Statistics 2024-05-27 Victor K. Khamesi , Niall M. Adams , Dean A. Bodenham , Edward A. K. Cohen

We develop a new method which extends Dynamic Mode Decomposition (DMD) to incorporate the effect of control to extract low-order models from high-dimensional, complex systems. DMD finds spatial-temporal coherent modes, connects local-linear…

Optimization and Control · Mathematics 2014-09-24 Joshua L. Proctor , Steven L. Brunton , J. Nathan Kutz