An empirical model of noise sources in subsonic jets

U Karban, B Bugeat, A Towne, L Lesshafft… - Journal of Fluid …, 2023 - cambridge.org
Modelling the noise emitted by turbulent jets is made difficult by their acoustic inefficiency:
only a tiny fraction of the near-field turbulent kinetic energy is propagated to the far field as …

Linstab2D: stability and resolvent analysis of compressible viscous flows in MATLAB

E Martini, O Schmidt - Theoretical and Computational Fluid Dynamics, 2024 - Springer
We present LinStab2D, an easy-to-use linear stability analysis MATLAB tool capable of
handling complex domains, performing temporal and spatial linear stability, and resolvent …

Bispectral mode decomposition of axisymmetrically and non-axisymmetrically forced turbulent jets

A Nekkanti, OT Schmidt, I Maia, P Jordan… - AIAA Aviation 2023 …, 2023 - arc.aiaa.org
View Video Presentation: https://doi. org/10.2514/6.2023-3651. vid Large-eddy simulations
(LES) of a turbulent unforced jet at Re=50,000 and M_j=0.4, and jets forced at azimuthal …

[PDF][PDF] Triadic nonlinear interactions and acoustics of forced versus unforced turbulent jets

A Nekkanti, I Maia, P Jordan, L Heidt… - … and Shear Flow …, 2022 - authors.library.caltech.edu
We explore the potential of bispectral mode decomposition (BMD) for physical discovery in
jet flows. BMD is a modal decomposition that is tailored to the extraction of flow structures …

Towards real-time reconstruction of velocity fluctuations in turbulent channel flow

R Arun, HJ Bae, BJ McKeon - Physical Review Fluids, 2023 - APS
We develop a framework for efficient streaming reconstructions of turbulent velocity
fluctuations from limited sensor measurements with the goal of enabling real-time …

Resolvent-based tools for optimal estimation and control via the Wiener–Hopf formalism

E Martini, J Jung, AVG Cavalieri, P Jordan… - Journal of Fluid …, 2022 - cambridge.org
The application of control tools to complex flows frequently requires approximations, such as
reduced-order models and/or simplified forcing assumptions, where these may be …

Nonlinear dynamics of vortex pairing in transitional jets

A Nekkanti, T Colonius, OT Schmidt - arXiv preprint arXiv:2407.16851, 2024 - arxiv.org
This study investigates the onset of linear instabilities and their later nonlinear interactions in
the shear layer of an initially-laminar jet using a combination of stability analysis and data …

On the role of eddy viscosity in resolvent analysis of turbulent jets

JGR von Saldern, OT Schmidt, P Jordan… - Journal of Fluid …, 2024 - cambridge.org
This study presents an approach to investigate the role of eddy viscosity in linearized mean-
field analysis of broadband turbulent flows. The procedure is based on spectral proper …

Real-Time Estimation of Jet-Surface Interaction Noise

M Mancinelli, P Jordan, A Lebedev - Flow, Turbulence and Combustion, 2024 - Springer
Motivated by the growing concerns for the noise emissions generated by the interaction
between the engine jet and the airframe surfaces consequent to the progressive increase of …

Gain in efficiency of jet receptivity to acoustic disturbances with increasing nozzle-lip thickness

C Bogey - Journal of Fluid Mechanics, 2024 - cambridge.org
The gain in efficiency of the receptivity of jets to acoustic disturbances as the nozzle lip is
thicker is investigated using numerical simulations. For that, axisymmetric acoustic pulses …