Article
Physics, Fluids & Plasmas
Mogeng Li, Woutijn J. Baars, Ivan Marusic, Nicholas Hutchins
Summary: We investigate the physics of the change in amplitude modulation coefficient in noncanonical wall-bounded flows using the inner-outer interaction model (IOIM). By deriving an analytical relationship between the amplitude modulation coefficient and IOIM parameters, we find that the coefficient increases with an increasing Reynolds number in a smooth-wall dataset. We apply this relationship to classify and interpret previous results on noncanonical turbulent boundary layers.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Engineering, Aerospace
A. A. Dhankarghare, T. Jayachandran, T. M. Muruganandam
Summary: This study combines a strut and a cavity into a strut cavity and compares it with a wall cavity using numerical simulations at different Mach numbers and aspect ratios. The results show that the wall cavity is more prone to oscillations compared to the strut cavity. The generation process of waves inside the cavity is revisited, where both the unstable shear layer and vortex shedding contribute to the wave generation in supersonic flows.
AEROSPACE SCIENCE AND TECHNOLOGY
(2022)
Article
Mechanics
S. Subbotin, N. Shmakova, V. Kozlov, E. Ermanyuk
Summary: This study experimentally investigates the fluid flow excited by inertial waves in a rotating annulus with a trapezoidal cross section. The experiment examines the interactions between inertial waves and zonal flows in the presence of the equivalent topographic beta-effect, and the dynamic behavior of the system under weak and strong forcing. The results show the generation of a zonal flow near a virtual axial cylinder at low wave intensity and the progression of non-linear regimes as forcing increases, leading to the emergence of additional discrete components and the development of a strong low-frequency component corresponding to Rossby waves.
Article
Mechanics
Kiran Jadhav, Abhilash J. Chandy
Summary: Large eddy simulations are performed for high-magnetic Reynolds number inhomogeneous magnetohydrodynamic flows. The simulations are validated using benchmark channel flow results and utilize a hybrid formulation of spectral and finite difference methods. The effect of velocity shear on magnetic field structures is explored for different interaction parameters. It is observed that for higher interaction parameters, the transition from laminar to turbulent is inhibited, while for lower values, a turbulent state is observed. The final state for the lower interaction parameter is characterized by a homogeneous distribution of large and small scales.
Article
Mechanics
Chang Liu, Dennice F. Gayme
Summary: The structured-singular-value-based approach proposed in this paper preserves certain input-output properties of the nonlinear forcing function to recover a larger range of key flow features. This method not only identifies flow structures predicted by traditional approaches but also captures oblique turbulent bands that have been observed in experiments and DNS.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
S. L. Tang, R. A. Antonia
Summary: The paper introduces a new hypothesis that suggests near-wall small-scale statistics, when suitably normalized, are independent of flow type as well as Reynolds and Peelet numbers. While the available wall turbulence direct numerical simulations data in a channel flow and a boundary layer provide good support for independence with respect to the Reynolds number, more data are needed to fully validate this hypothesis, particularly for higher-order statistics and other types of wall flows with different surface conditions.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Qing-fu Zhang, Chong Pan, Jin-jun Wang
Summary: This work investigates the symmetry-breaking phenomenon in large-to-small amplitude modulation (AM) of wall-bounded turbulence. By using a multi-component variational mode decomposition method, the volumetric velocity fields of a spatially developing turbulent boundary layer obtained from direct numerical simulation are decomposed into four three-dimensional intrinsic mode functions (IMFs). It is found that there is an asymmetry in the AM effect, and a method is proposed to remove this asymmetry and improve the universality of small-scale turbulent motions.
Article
Mechanics
C. Chen, L. He
Summary: Recent findings on wall-bounded turbulence have led to the development of a new modelling method to capture the influence of large-scale coherent structures and scale-interaction on near-wall turbulence. This paper presents a two-scale approach to simulate this influence and validates its effectiveness.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Yu Lv, Xinyi L. D. Huang, Xiaolei Yang, Xiang I. A. Yang
Summary: The paper addresses performance issues of wall-modeled large-eddy simulation (WMLES) by integrating wall models into LES solvers, abandoning stand-alone wall-model solvers. By employing physics-inspired bases for LES solution reconstruction in the wall-adjacent cell, the computational framework effortlessly accounts for non-equilibrium effects in high-order codes, with channel flow for proof of concept and periodic hill for validation.
Article
Computer Science, Interdisciplinary Applications
Sergio Pirozzoli, Paolo Orlandi
Summary: This paper proposes a new DNS method for wall-bounded flows, using numerical simulations to derive optimal parameters and grid spacing, and providing a specific prescription for the number of grid points and grid clustering needed for accurate results. The conclusions are supported by high Reynolds number DNS, demonstrating the presence of a near logarithmic layer in the mean velocity profile.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Mechanics
S. Blanchard, N. Odier, L. Gicquel, B. Cuenot, F. Nicoud
Summary: In the framework of wall-modeled large-eddy simulation (WMLES), the static Smagorinsky model predicts efficiently the wall shear stress, while more advanced static models like WALE or Sigma fail in this aspect. Smagorinsky is known to be too dissipative in the bulk flow and purely sheared flows, whereas the other models are better suited for near-wall flows.
Article
Mathematics, Interdisciplinary Applications
Yves Pomeau, Martine Le Berre
Summary: We propose a scenario for the formation of localized turbulent spots in transition flows, which does not require the addition of random noise term in the equations. We derive the instability threshold for generalized complex Ginzburg-Landau equation and show that the dynamics is driven by the phase of the complex amplitude. Above the Benjamin-Feir threshold, the fluctuations of the intensity are smaller than those of the phase and slaved to the phase; below the threshold, the transition becomes of the mean-field type and leads to pulse-like patterns.
CHAOS SOLITONS & FRACTALS
(2023)
Article
Mechanics
Hai-Ning Wang, Wei-Xi Huang, Chun-Xiao Xu
Summary: The study aims to supplement near-wall small-scale turbulence fluctuations with synthetic flow fields generated from a universal model, thereby reducing computational cost. The generated flow is statistically consistent with and structurally similar to authentic MFU.
Article
Mechanics
Matthew A. Subrahmanyam, Brian J. Cantwell, Juan J. Alonso
Summary: This paper introduces a mixing length model for turbulent shear stress in pipe flow and provides a universal velocity profile. The velocity profile accurately approximates both experimental and simulated data in various flow conditions, making it significant for studying the statistical properties of flow.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Multidisciplinary Sciences
Thomas Howson
Summary: Oscillatory power and MHD waves in the solar corona have attracted great interest in the context of coronal heating problem. However, uncertainties remain in estimating their energy flux and their contribution to the coronal energy budget. The dissipations of wave energy and the generation of small-scale heating are important issues. MHD turbulence has been shown to efficiently dissipate large quantities of energy and drive complex turbulent behavior in the solar corona.
Article
Automation & Control Systems
Neil K. Dhingra, Sei Zhen Khong, Mihailo R. Jovanovic
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2019)
Article
Physics, Fluids & Plasmas
Wei Ran, Armin Zare, M. J. Philipp Hack, Mihailo R. Jovanovic
PHYSICAL REVIEW FLUIDS
(2019)
Editorial Material
Automation & Control Systems
Jorge Cortes, Magnus Egerstedt, Mihailo R. Jovanovic
IEEE CONTROL SYSTEMS MAGAZINE
(2019)
Article
Physics, Fluids & Plasmas
Wei Ran, Armin Zare, M. J. Philipp Hack, Mihailo R. Joyanovic
PHYSICAL REVIEW FLUIDS
(2019)
Editorial Material
Automation & Control Systems
M. Chertkov, M. Jovanovic, B. Lesieutre, S. Low, P. van Hentenryck, L. Wehenkel
IEEE TRANSACTIONS ON CONTROL OF NETWORK SYSTEMS
(2019)
Article
Mechanics
Anubhav Dwivedi, G. S. Sidharth, Joseph W. Nichols, Graham Candler, Mihailo R. Jovanovic
JOURNAL OF FLUID MECHANICS
(2019)
Proceedings Paper
Automation & Control Systems
Wei Ran, Armin Zare, Mihailo R. Jovanovic
2019 IEEE 58TH CONFERENCE ON DECISION AND CONTROL (CDC)
(2019)
Proceedings Paper
Automation & Control Systems
Hesameddin Mohammadi, Armin Zare, Mahdi Soltanolkotabi, Mihailo R. Jovanovic
2019 IEEE 58TH CONFERENCE ON DECISION AND CONTROL (CDC)
(2019)
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Automation & Control Systems
Neil K. Dhingra, Marcello Colombino, Mihailo R. Jovanovic
IEEE TRANSACTIONS ON CONTROL OF NETWORK SYSTEMS
(2019)
Proceedings Paper
Automation & Control Systems
Armin Zare, Mihailo R. Jovanovic
2018 IEEE CONFERENCE ON DECISION AND CONTROL (CDC)
(2018)
Proceedings Paper
Automation & Control Systems
Hesameddin Mohammadi, Meisam Razaviyayn, Mihailo R. Jovanovic
2018 IEEE CONFERENCE ON DECISION AND CONTROL (CDC)
(2018)
Proceedings Paper
Automation & Control Systems
Dongsheng Ding, Bin Hu, Neil K. Dhingra, Mihailo R. Jovanovic
2018 IEEE CONFERENCE ON DECISION AND CONTROL (CDC)
(2018)
Proceedings Paper
Automation & Control Systems
Sepideh Hassan-Moghaddam, Mihailo R. Jovanovic
2018 IEEE CONFERENCE ON DECISION AND CONTROL (CDC)
(2018)
Proceedings Paper
Automation & Control Systems
Sepideh Hassan-Moghaddam, Mihailo R. Jovanovic
2018 IEEE CONFERENCE ON DECISION AND CONTROL (CDC)
(2018)
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Automation & Control Systems
Sepideh Hassan-Moghaddam, Mihailo R. Jovanovic
IEEE TRANSACTIONS ON CONTROL OF NETWORK SYSTEMS
(2018)
