2023

  • [PDF] [DOI] Nekkanti, A. and O. T. Schmidt. “Gappy spectral proper orthogonal decomposition.” Journal of computational physics 478 (2023): 111950.
    [Bibtex] 
    @Article{nekkantischmidt_2023_jcp,
author = {A. Nekkanti and O. T. Schmidt},
journal = {Journal of Computational Physics},
title = {Gappy spectral proper orthogonal decomposition},
year = {2023},
issn = {0021-9991},
pages = {111950},
volume = {478},
abstract = {Experimental spatio-temporal flow data often contain gaps or other types of undesired artifacts. To reconstruct flow data in the compromised or missing regions, a data completion method based on spectral proper orthogonal decomposition (SPOD) is developed. The algorithm leverages the temporal correlation of the SPOD modes with preceding and succeeding snapshots, and their spatial correlation with the surrounding data at the same time instant. For each gap, the algorithm first computes the SPOD of the remaining, unaffected data. In the next step, the compromised data are projected onto the basis of the SPOD modes. This corresponds to a local inversion of the SPOD problem and yields expansion coefficients that permit the reconstruction in the affected regions. This local reconstruction is successively applied to each gap. After all gaps are filled in, the procedure is repeated in an iterative manner until convergence. This method is demonstrated on two examples: direct numerical simulation of laminar flow around a cylinder, and time-resolved PIV data of turbulent cavity flow obtained by Zhang et al. (2019) [47]. Randomly added gaps correspond to 1%, 5%, and 20% of data loss. Even for 20% data corruption, and in the presence of measurement noise in the experimental data, the algorithm recovers 97% and 80% of the original data in the corrupted regions of the simulation and PIV data, respectively. These values are higher than those achieved by established methods like gappy POD and Kriging.},
doi = {https://doi.org/10.1016/j.jcp.2023.111950},
file = {:NekkantiSchmidt_2023_JCP.pdf:PDF},
keywords = {Gappy POD, Data reconstruction, Data assimilation, Kriging, Spectral proper orthogonal decomposition, Particle image velocimetry},
url = {https://www.sciencedirect.com/science/article/pii/S0021999123000451},
}
  • [PDF] [DOI] Chu, T. and O. T. Schmidt. “Rbf-fd discretization of the navier-stokes equations on scattered but staggered nodes.” Journal of computational physics 474 (2023): 111756.
    [Bibtex] 
    @Article{chuschmidt_2022_jcp,
author = {Chu, T. and Schmidt, O. T.},
journal = {Journal of Computational Physics},
title = {RBF-FD discretization of the Navier-Stokes equations on scattered but staggered nodes},
year = {2023},
issn = {0021-9991},
pages = {111756},
volume = {474},
abstract = {A semi-implicit fractional-step method that uses a staggered node layout and radial basis function-finite differences (RBF-FD) to solve the incompressible Navier-Stokes equations is developed. Polyharmonic splines (PHS) with polynomial augmentation (PHS+poly) are used to construct the global differentiation matrices. A systematic parameter study identifies a combination of stencil size, PHS exponent, and polynomial degree that minimizes the truncation error for a wave-like test function on scattered nodes. Classical modified wavenumber analysis is extended to RBF-FDs on heterogeneous node distributions and used to confirm that the accuracy of the selected 28-point stencil is comparable to that of spectral-like, 6th-order Padé-type finite differences. The Navier-Stokes solver is demonstrated on two benchmark problems, internal flow in a lid-driven cavity in the Reynolds number regime 102≤Re≤104, and open flow around a cylinder at Re=100 and 200. The combination of grid staggering and careful parameter selection facilitates accurate and stable simulations at significantly lower resolutions than previously reported, using more compact RBF-FD stencils, without special treatment near solid walls, and without the need for hyperviscosity or other means of regularization.},
doi = {https://doi.org/10.1016/j.jcp.2022.111756},
file = {:ChuSchmidt_2022_JCP.pdf:PDF},
keywords = {RBF-FD, Polyharmonic splines, Polynomial augmentation, Navier-Stokes, Fractional-step, Staggered grid},
url = {https://authors.elsevier.com/a/1gAx3508HsaX-},
}

2022

  • [PDF] [DOI] Schmidt, O. T.. “Spectral proper orthogonal decomposition using multitaper estimates.” Theoretical and computational fluid dynamics (2022): 1–14.
    [Bibtex] 
    @Article{schmidt_2022_tcfd,
author = {Schmidt, O. T.},
journal = {Theoretical and Computational Fluid Dynamics},
title = {{Spectral proper orthogonal decomposition using multitaper estimates}},
year = {2022},
issn = {0935-4964},
pages = {1--14},
abstract = {{The use of multitaper estimates for spectral proper orthogonal decomposition (SPOD) is explored. Multitaper and multitaper-Welch estimators that use discrete prolate spheroidal sequences (DPSS) as orthogonal data windows are compared to the standard SPOD algorithm that exclusively relies on weighted overlapped segment averaging, or Welch’s method, to estimate the cross-spectral density matrix. Two sets of turbulent flow data, one experimental and the other numerical, are used to discuss the choice of resolution bandwidth and the bias-variance tradeoff. Multitaper-Welch estimators that combine both approaches by applying orthogonal tapers to overlapping segments allow for flexible control of resolution, variance, and bias. At additional computational cost but for the same data, multitaper-Welch estimators provide lower variance estimates at fixed frequency resolution or higher frequency resolution at similar variance compared to the standard algorithm.}},
doi = {10.1007/s00162-022-00626-x},
file = {:Schmidt_2022_TCFD.pdf:PDF},
url = {https://rdcu.be/cUtP3},
}
  • [PDF] [DOI] Lowell, Edward, Oliver Schmidt, Frantisek Batysta, Issa Tamer, and Thomas Spinka. “Towards optimal gas cooling with minimal aero-optical distortion for a laser amplifier head.” Aiaa paper 2022-3265 (2022).
    [Bibtex] 
    @Article{lowelletal_2022_aiaa,
author = {Edward Lowell and Oliver Schmidt and Frantisek Batysta and Issa Tamer and Thomas Spinka},
journal = {AIAA Paper 2022-3265},
title = {Towards Optimal Gas Cooling with Minimal Aero-optical Distortion for a Laser Amplifier Head},
year = {2022},
abstract = {View Video Presentation: https://doi.org/10.2514/6.2022-3265.vid Next-generation, high-peak-power, ultrashort-pulse lasers have the potential to efficiently deliver the high-average-power outputs required by many emerging technologies and areas of research. The combination of large size and low-repetition rates of previous-generation lasers make their effective and widespread usage impractical. The critical step in an effort to increase the repetition rate is a proper management of the waste heat generated in the laser gain medium. The current paper presents a computational approach with which to improve upon current gas-cooled amplifier designs; the ultimate goal being to optimize the head geometry for efficient cooling while maintaining minimal aero-optical distortion. This approach consists of several components, the focus of which are low-fidelity RANS simulations, and high-fidelity LES and aero-optical simulations. Preliminary results indicate that these components interface properly in handling the prescribed base case, and lay the groundwork for continued progress towards simulating, modeling, and optimizing the amplifier head for efficient cooling.},
doi = {10.2514/6.2022-3265},
eprint = {https://arc.aiaa.org/doi/pdf/10.2514/6.2022-3265},
file = {:LowellEtAl_2022_AIAA.pdf:PDF},
url = {https://arc.aiaa.org/doi/abs/10.2514/6.2022-3265},
}
  • [PDF] [DOI] Yeung, B. C. Y., O. T. Schmidt, and G. A. Brès. “Three-dimensional spectral pod of supersonic twin-rectangular jet flow.” Aiaa paper 2022-3345 (2022).
    [Bibtex] 
    @Article{yeungetal_2022_aiaa,
author = {B. C. Y. Yeung and O. T. Schmidt and G. A. Brès},
journal = {AIAA Paper 2022-3345},
title = {Three-Dimensional Spectral POD of Supersonic Twin-Rectangular Jet Flow},
year = {2022},
abstract = {View Video Presentation: https://doi.org/10.2514/6.2022-3345.vid The statistical analysis of non-axisymmetric turbulent jets using spectral proper orthogonal decomposition (SPOD) is computationally costly; in particular, their non-axisymmetry precludes Fourier decomposition of the three-dimensional flow field into two-dimensional azimuthal modes. Jets in the dihedral group \$D\_2\$, including rectangular, elliptic, and twin jets, are invariant under reflection about their major and minor axes. For these jets, we propose an SPOD workflow that exploits their \$D\_2\$ geometrical symmetry to obtain a reduction in computational effort, accelerate statistical convergence, and improve the interpretability of results. We decompose the three-dimensional snapshots into four symmetry components. For each symmetry component, we independently perform SPOD on one quadrant of the domain. We demonstrate an application of this \$D\_2\$-symmetric SPOD workflow on a large-eddy simulation of a twin-rectangular supersonic jet. Our analysis indicates that the twin jet exhibits screech at Strouhal number 0.3, and that this screech is dominated by components which are antisymmetric along the minor axis. These observations are consistent with the results from companion experiments at Ohio State University. Furthermore, the same workflow is used to analyze the symmetry-dependence of far-field acoustics at low and high frequencies.},
doi = {10.2514/6.2022-3345},
eprint = {https://arc.aiaa.org/doi/pdf/10.2514/6.2022-3345},
file = {:YeungEtAl_2022_AIAA.pdf:PDF},
url = {https://arc.aiaa.org/doi/abs/10.2514/6.2022-3345},
}
  • [PDF] [DOI] Chu, T. and O. T. Schmidt. “Mesh-free rbf-based discretizations for hydrodynamic stability analysis.” Aiaa paper 2022-4098 (2022).
    [Bibtex] 
    @Article{chuschmidt_2022_aiaa,
author = {T. Chu and O. T. Schmidt},
journal = {AIAA Paper 2022-4098},
title = {Mesh-free RBF-based discretizations for hydrodynamic stability analysis},
year = {2022},
abstract = { View Video Presentation: https://doi.org/10.2514/6.2022-4098.vid Radial basis function-based finite differences (RBF-FD) are used to develop a high-order mesh-free hydrodynamic stability analysis tool for complex geometries. Polyharmonic spline RBFs with polynomial augmentation (PHS+poly) are used to construct the discrete linearized Navier-Stokes and resolvent operators on arbitrarily scattered nodes. The PHS+poly discretization is shown to yield accurate, stable, and computationally efficient discretizations of the large hydrodynamic stability matrix problems arising in two-dimensional classical linear theory and resolvent analysis. The mean-flow stability of the wake behind a cylinder in the vicinity of the critical point is studied using both theories. The predicted flow instabilities, including the vortex shedding frequency and associated coherent structures, closely match those reported in the literature. },
doi = {10.2514/6.2022-4098},
eprint = {https://arc.aiaa.org/doi/pdf/10.2514/6.2022-4098},
file = {:ChuSchmidt_2022_AIAA.pdf:PDF},
url = {https://arc.aiaa.org/doi/abs/10.2514/6.2022-4098},
}
  • [PDF] [DOI] Nidhan, S., O. T. Schmidt, and S. Sarkar. “Analysis of coherence in turbulent stratified wakes using spectral proper orthogonal decomposition.” Journal of fluid mechanics 934 (2022): A12.
    [Bibtex] 
    @Article{nidhanetal_2022_jfm,
author = {Nidhan, S. and Schmidt, O. T. and Sarkar, S.},
journal = {Journal of Fluid Mechanics},
title = {Analysis of coherence in turbulent stratified wakes using spectral proper orthogonal decomposition},
year = {2022},
pages = {A12},
volume = {934},
doi = {10.1017/jfm.2021.1096},
file = {:NidhanEtAl_2022_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}

2021

  • [PDF] [DOI] Brès, G. A., B. Yeung, O. T. Schmidt, A. G. Isfahani, N. J. Webb, M. Samimy, and T. Colonius. “Towards large-eddy simulations of supersonic jets from twin rectangular nozzle with plasma actuation.” Aiaa paper 2021-2154 (2021).
    [Bibtex] 
    @Article{bresetal_2021_aiaa,
author = {G. A. Brès and B. Yeung and O. T. Schmidt and A. G. Isfahani and N. J. Webb and M. Samimy and T. Colonius},
journal = {AIAA Paper 2021-2154},
title = {Towards large-eddy simulations of supersonic jets from twin rectangular nozzle with plasma actuation},
year = {2021},
abstract = {View Video Presentation: https://doi.org/10.2514/6.2021-2154.vidLarge-eddy simulation of a jet issuing from rectangular nozzles of aspect ratio 2 is performed. The nozzles are operating at their nominal design Mach number of 1.5. This operating condition and the geometry match those of the companion experiment conducted at Ohio State University. The preliminary results show good agreement with near-field and far-field noise measurements in terms of broadband levels and predictions of screech tone frequencies and amplitudes. In particular, the main noise radiation towards the aft angles and the overall sound pressure level directivity are within 1dB for most relevant frequencies and angles. For future simulations of active control, a numerical model of a localized arc filament plasma actuator is implemented and tested in a small test domain inside one of the nozzles. A grid resolution study is conducted to investigate the minimum grid resolution required for correct energy transport within the boundary layer.},
doi = {10.2514/6.2021-2154},
eprint = {https://arc.aiaa.org/doi/pdf/10.2514/6.2021-2154},
file = {:BresEtAl_AIAA_2021.pdf:PDF},
url = {https://arc.aiaa.org/doi/abs/10.2514/6.2021-2154},
}
  • [PDF] [DOI] Chu, T. and O. T. Schmidt. “An rbf-based finite difference discretization of the navier-stokes equations: error analysis and application to lid-driven cavity flow.” Aiaa paper 2021-2743 (2021).
    [Bibtex] 
    @Article{chuschmidt_2021_aiaa,
author = {Chu, T. and Schmidt, O. T.},
journal = {AIAA Paper 2021-2743},
title = {An RBF-based finite difference discretization of the Navier-Stokes equations: error analysis and application to lid-driven cavity flow},
year = {2021},
abstract = {View Video Presentation: https://doi.org/10.2514/6.2021-2743.vidRadial basis function-finite differences (RBF-FD) are used to solve the incompressible Navier-Stokes equations on scattered nodes. We present a semi-implicit fractional-step method that uses a staggered grid arrangement. The RBF-QR method devised by Fornberg and Piret[1] is used to obtain the RBF-FD weights for the spatial derivatives. We propose a rigorous error analysis strategy to identify optimal combinations of the shape parameter, ε, and the stencil size,n. A modified wavenumber analysis shows that the accuracy of the RBF differentiation matrices based on the optimal parameters is comparable to 4th-order Padé-type finite differences, for both first and second derivatives. The internal flow in a lid-driven cavity is studied as an example. We demonstrate that stable solutions are obtained without the need for hyperviscosity.},
doi = {10.2514/6.2021-2743},
eprint = {https://arc.aiaa.org/doi/pdf/10.2514/6.2021-2743},
file = {:ChuSchmidt_AIAA_2021.pdf:PDF},
url = {https://arc.aiaa.org/doi/abs/10.2514/6.2021-2743},
}
  • [PDF] [DOI] Maia, I., P. Jordan, L. Heidt, T. Colonius, A. Nekkanti, and O. T. Schmidt. “Nonlinear dynamics of forced wavepackets in turbulent jets.” Aiaa paper 2021-2277 (2021).
    [Bibtex] 
    @Article{maiaetal_2021_aiaa,
author = {I. Maia and P. Jordan and L. Heidt and T. Colonius and A. Nekkanti and O. T. Schmidt},
journal = {AIAA Paper 2021-2277},
title = {Nonlinear dynamics of forced wavepackets in turbulent jets},
year = {2021},
abstract = {View Video Presentation: https://doi.org/10.2514/6.2021-2277.vidWe study the dynamics of harmonically-forced jets under different forcing amplitudes covering linear and nonlinear response regimes. Using a combination of Particle Image Velocimetry (PIV) measurements, Spectral Proper Orthogonal Decomposition (SPOD) and Bispectral Mode Decomposition (BMD), we educe coherent structures on the different forcing regimes and analyse how strong nonlinear interactions affect their dynamics. The forced jets provide a simplified scenario where energy exchange between frequencies can be traced back to a few prominent triadic interactions. These are identified through the mode bispectrum and the associated BMD modes are found to be in good agreement with the most energetic structures computed through SPOD. The mode bispectrum also provides insight into the relative importance of linear and nonlinear mechanisms, with respect to the mean of the forced jet, in determining the amplitudes of velocity fluctuations at the forcing frequency and its harmonics. Unforced jets have a broad signature in the bispectrum, reflecting the broadband nature of nonlinear energy exchange in the unforced jets.},
doi = {10.2514/6.2021-2277},
eprint = {https://arc.aiaa.org/doi/pdf/10.2514/6.2021-2277},
file = {:MaiaEtAl_AIAA_2021.pdf:PDF},
url = {https://arc.aiaa.org/doi/abs/10.2514/6.2021-2277},
}
  • [PDF] [DOI] Nekkanti, A. and O. T. Schmidt. “Frequency–time analysis, low-rank reconstruction and denoising of turbulent flows using spod.” Journal of fluid mechanics 926 (2021): A26.
    [Bibtex] 
    @Article{nekkantischmidt_2021_jfm,
author = {Nekkanti, A. and Schmidt, O. T.},
journal = {Journal of Fluid Mechanics},
title = {Frequency–time analysis, low-rank reconstruction and denoising of turbulent flows using SPOD},
year = {2021},
pages = {A26},
volume = {926},
doi = {10.1017/jfm.2021.681},
file = {:NekkantiSchmidt_2021_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Chu, T. and O. T. Schmidt. “A stochastic spod-galerkin model for broadband turbulent flows.” Theoretical and computational fluid dynamics (2021).
    [Bibtex] 
    @Article{chuschmidt_2021_tcfd,
author = {Chu, T. and Schmidt, O. T.},
journal = {Theoretical and Computational Fluid Dynamics},
title = {A stochastic SPOD-Galerkin model for broadband turbulent flows},
year = {2021},
issn = {1432-2250},
abstract = {The use of spectral proper orthogonal decomposition (SPOD) to construct low-order models for broadband turbulent flows is explored. The choice of SPOD modes as basis vectors is motivated by their optimality and space-time coherence properties for statistically stationary flows. This work follows the modeling paradigm that complex nonlinear fluid dynamics can be approximated as stochastically forced linear systems. The proposed stochastic two-level SPOD-Galerkin model governs a compound state consisting of the modal expansion coefficients and forcing coefficients. In the first level, the modal expansion coefficients are advanced by the forced linearized Navier-Stokes operator under the linear time-invariant assumption. The second level governs the forcing coefficients, which compensate for the offset between the linear approximation and the true state. At this level, least squares regression is used to achieve closure by modeling nonlinear interactions between modes. The statistics of the remaining residue are used to construct a dewhitening filter that facilitates the use of white noise to drive the model. If the data residue is used as the sole input, the model accurately recovers the original flow trajectory for all times. If the residue is modeled as stochastic input, then the model generates surrogate data that accurately reproduces the second-order statistics and dynamics of the original data. The stochastic model uncertainty, predictability, and stability are quantified analytically and through Monte Carlo simulations. The model is demonstrated on large eddy simulation data of a turbulent jet at Mach number $$M=0.9$$and Reynolds number $$\mathrm {Re}_D\approx 10^6$$.},
doi = {10.1007/s00162-021-00588-6},
file = {:ChuSchmidt_2021_TCFD.pdf:PDF},
refid = {Chu2021},
url = {https://doi.org/10.1007/s00162-021-00588-6},
}
  • [PDF] [DOI] Pickering, E., G. Rigas, O. T. Schmidt, D. Sipp, and T. Colonius. “Optimal eddy viscosity for resolvent-based models of coherent structures in turbulent jets.” Journal of fluid mechanics 917 (2021): A29.
    [Bibtex] 
    @Article{pickeringetal_2021_jfm,
author = {Pickering, E. and Rigas, G. and Schmidt, O. T. and Sipp, D. and Colonius, T.},
journal = {Journal of Fluid Mechanics},
title = {Optimal eddy viscosity for resolvent-based models of coherent structures in turbulent jets},
year = {2021},
pages = {A29},
volume = {917},
doi = {10.1017/jfm.2021.232},
file = {:PickeringEtAl_2021_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Edgington-Mitchell, D., T. Wang, P. Nogueira, O. T. Schmidt, V. Jaunet, D. Duke, P. Jordan, and A. Towne. “Waves in screeching jets.” Journal of fluid mechanics 913 (2021): A7.
    [Bibtex] 
    @Article{edgingtonmitchelletal_2021_jfm,
author = {Edgington-Mitchell, D. and Wang, T. and Nogueira, P. and Schmidt, O. T. and Jaunet, V. and Duke, D. and Jordan, P. and Towne, A.},
journal = {Journal of Fluid Mechanics},
title = {Waves in screeching jets},
year = {2021},
pages = {A7},
volume = {913},
doi = {10.1017/jfm.2020.1175},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Hack, M. J. P. and O. T. Schmidt. “Extreme events in wall turbulence.” Journal of fluid mechanics 907 (2021): A9.
    [Bibtex] 
    @Article{hackschmidt_2020_jfm,
author = {Hack, M. J. P. and Schmidt, O. T.},
journal = {Journal of Fluid Mechanics},
title = {Extreme events in wall turbulence},
year = {2021},
pages = {A9},
volume = {907},
doi = {10.1017/jfm.2020.798},
file = {:HackSchmidt_2020_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}

2020

  • [PDF] [DOI] Nekkanti, A. and O. T. Schmidt. “Modal analysis of the directivity of acoustic emissions from wavepackets in turbulent jets.” Aiaa paper 2020-0745 (2020).
    [Bibtex] 
    @Article{nekkantischmidt_2020_aiaa,
author = {Nekkanti, A. and Schmidt, O. T.},
journal = {AIAA Paper 2020-0745},
title = {Modal analysis of the directivity of acoustic emissions from wavepackets in turbulent jets},
year = {2020},
abstract = {The directivity of noise from three large-eddy simulations of turbulent jets at Mach 0.7, 0.9 and 1.5 and the first three azimuthal wavenumbers is investigated using spectral proper orthogonal decomposition (SPOD). First, a weighting function for the pressure 2-norm that is localized to the far-field is employed to educe the overall most energetic radiation patterns. Second, we isolate radiation patterns to specific jet inlet angles by restricting the spatial weighting to small rectangular regions in the far-field. The most energetic radiation pattern for all cases and relevant frequencies is a single superdirective acoustic beam in the downstream direction. The source region of these beams is traced back to the end of the potential core for low frequencies and the shear-layer region for higher frequencies. In the sideline direction to low angles, the acoustic patterns consist of waves that propagate upstream or perpendicular to the jet axis. The sideline radiation patterns are found to originate from the same source locations as the dominant superdirective beams. Inspection of the SPOD modes reveals that sideline radiation is directly slaved to directive downstream radiation. These results indicate that large-scale coherent structures are the dominant source of acoustic radiation to all the angles.},
doi = {10.2514/6.2020-0745},
eprint = {https://arc.aiaa.org/doi/pdf/10.2514/6.2020-0745},
file = {:NekkantiSchmidt_2020_AIAA.pdf:PDF},
url = {https://arc.aiaa.org/doi/abs/10.2514/6.2020-0745},
}
  • [PDF] [DOI] Nidhan, S., K. Chongsiripinyo, O. T. Schmidt, and S. Sarkar. “Spectral proper orthogonal decomposition analysis of the turbulent wake of a disk at Re=50000.” Physical review fluids 5.12 (2020): 124606.
    [Bibtex] 
    @Article{nidhanetal_2020_prf,
author = {Nidhan, S. and Chongsiripinyo, K. and Schmidt, O. T. and Sarkar, S.},
journal = {Physical Review Fluids},
title = {{Spectral proper orthogonal decomposition analysis of the turbulent wake of a disk at Re=50000}},
year = {2020},
number = {12},
pages = {124606},
volume = {5},
doi = {10.1103/PhysRevFluids.5.124606},
file = {:NidhanEtAl_2020_PRF.pdf:PDF},
publisher = {APS},
}
  • [PDF] [DOI] Antonialli, L. A., A. V. G. Cavalieri, O. T. Schmidt, T. Colonius, P. Jordan, A. Towne, and G. A. Brès. “Amplitude scaling of wave packets in turbulent jets.” Aiaa journal (2020): 1-10.
    [Bibtex] 
    @Article{antoniallietal_2020_aiaaj,
author = {Antonialli, L. A. and Cavalieri, A. V. G. and Schmidt, O. T. and Colonius, T. and Jordan, P. and Towne, A. and Br{\`e}s, G. A.},
journal = {AIAA Journal},
title = {Amplitude Scaling of Wave Packets in Turbulent Jets},
year = {2020},
number = {0},
pages = {1-10},
volume = {0},
abstract = {This paper studies the amplitude of large-scale coherent wave-packet structures in jets, modeled by the parabolized stability equations (PSEs). Linear PSEs can retrieve the shape of the wave packets, but linearity leads to solutions with a free amplitude, which has traditionally been obtained in an ad hoc manner using limited data. We systematically determine the free amplitude as a function of frequency and azimuthal wave number by comparing the fluctuation fields retrieved from PSEs with coherent structures educed from large-eddy simulation data using spectral proper orthogonal decomposition. The wave-packet amplitude is shown to decay exponentially with the Strouhal number for axisymmetric and helical modes at both Mach numbers considered in the study: 0.4 and 0.9. Analytical fit functions are proposed, and the scaled wave packets provide reasonable reconstructions of pressure and velocity spectra on the jet centerline and lip line over a range of streamwise positions.},
doi = {10.2514/1.J059599},
eprint = {https://doi.org/10.2514/1.J059599},
url = {https://doi.org/10.2514/1.J059599},
}
  • [PDF] [DOI] Schmidt, O. T.. “Bispectral mode decomposition of nonlinear flows.” Nonlinear dynamics 102(4) (2020): 2479-25013.
    [Bibtex] 
    @Article{schmidt_2020_nody,
author = {Schmidt, O. T.},
journal = {Nonlinear Dynamics},
title = {{Bispectral mode decomposition of nonlinear flows}},
year = {2020},
issn = {0924-090X},
number = {102(4)},
pages = {2479-25013},
doi = {10.1007/s11071-020-06037-z},
file = {:Schmidt_2020_NODY.pdf:PDF},
}
  • [PDF] [DOI] Nekkanti, A. and O. T. Schmidt. “Modal analysis of acoustic directivity in turbulent jets.” Aiaa journal (2020): 1-12.
    [Bibtex] 
    @Article{nekkantischmidt_2020_aiaaj,
author = {Nekkanti, A. and Schmidt, O. T.},
journal = {AIAA Journal},
title = {Modal Analysis of Acoustic Directivity in Turbulent Jets},
year = {2020},
pages = {1-12},
doi = {10.2514/1.J059425},
eprint = {https://doi.org/10.2514/1.J059425},
file = {:NekkantiSchmidt_2020_AIAAJ.pdf:PDF},
url = {https://doi.org/10.2514/1.J059425},
}
  • [PDF] [DOI] Pickering, E., G. Rigas, P. A. S. Nogueira, A. V. G. Cavalieri, O. T. Schmidt, and T. Colonius. “Lift-up, Kelvin–Helmholtz and Orr mechanisms in turbulent jets.” Journal of fluid mechanics 896 (2020): A2.
    [Bibtex] 
    @Article{pickeringetal_2020_jfm,
author = {Pickering, E. and Rigas, G. and Nogueira, P. A. S. and Cavalieri, A. V. G. and Schmidt, O. T. and Colonius, T.},
journal = {Journal of Fluid Mechanics},
title = {{Lift-up, Kelvin–Helmholtz and Orr mechanisms in turbulent jets}},
year = {2020},
pages = {A2},
volume = {896},
doi = {10.1017/jfm.2020.301},
publisher = {Cambridge University Press},
}
  • [PDF] Brouzet, D., A. Haghiri, M. Talei, M. J. Brear, O. T. Schmidt, G. Rigas, and T. Colonius. “Role of coherent structures in turbulent premixed flame acoustics.” Aiaa journal 58.6 (2020): 2635-2642.
    [Bibtex] 
    @Article{brouzetetal_2020_aiaaj,
author = {Brouzet, D. and Haghiri, A. and Talei, M. and Brear, M. J. and Schmidt, O. T. and Rigas, G. and Colonius, T.},
journal = {AIAA Journal},
title = {Role of Coherent Structures in Turbulent Premixed Flame Acoustics},
year = {2020},
number = {6},
pages = {2635-2642},
volume = {58},
publisher = {American Institute of Aeronautics and Astronautics},
}
  • [PDF] Schmidt, O. T. and T. Colonius. “Guide to spectral proper orthogonal decomposition.” Aiaa journal (2020): 1–11.
    [Bibtex] 
    @article{schmidtcolonius_2020_aiaaj,
title={Guide to Spectral Proper Orthogonal Decomposition},
author={Schmidt, O. T. and Colonius, T.},
journal={AIAA Journal},
pages={1--11},
year={2020},
publisher={American Institute of Aeronautics and Astronautics}
}

2019

  • [PDF] [DOI] Selent, B., C. Wenzel, U. Rist, and O. T. Schmidt. “Turbulent inflow generation by resolvent mode forcing.” New results in numerical and experimental fluid mechanics xii (2019): 110–119.
    [Bibtex] 
    @Article{SelentEtAl_2019_NRNEFM,
author = {Selent, B. and Wenzel, C. and Rist, U. and Schmidt, O. T.},
title = {Turbulent Inflow Generation by Resolvent Mode Forcing},
journal = {New Results in Numerical and Experimental Fluid Mechanics XII},
year = {2019},
pages = {110--119},
organization = {Springer},
doi = {10.1007/978-3-030-25253-3_11},
}
  • [PDF] [DOI] Schmidt, O. T., G. Mengaldo, G. Balsamo, and N. P. Wedi. “Spectral empirical orthogonal function analysis of weather and climate data.” Monthly weather review 147.8 (2019): 2979-2995.
    [Bibtex] 
    @Article{schmidtetal_2019_mwr,
author = {Schmidt, O. T. and Mengaldo, G. and Balsamo, G. and Wedi, N. P.},
title = {Spectral Empirical Orthogonal Function Analysis of Weather and Climate Data},
journal = {Monthly Weather Review},
year = {2019},
volume = {147},
number = {8},
pages = {2979-2995},
abstract = { AbstractWe apply spectral empirical orthogonal function (SEOF) analysis to educe climate patterns as dominant spatiotemporal modes of variability from reanalysis data. SEOF is a frequency-domain variant of standard empirical orthogonal function (EOF) analysis, and computes modes that represent the statistically most relevant and persistent patterns from an eigendecomposition of the estimated cross-spectral density matrix (CSD). The spectral estimation step distinguishes the approach from other frequency-domain EOF methods based on a single realization of the Fourier transform, and results in a number of desirable mathematical properties: at each frequency, SEOF yields a set of orthogonal modes that are optimally ranked in terms of variance in the L2 sense, and that are coherent in both space and time by construction. We discuss the differences between SEOF and other competing approaches, as well as its relation to dynamical modes of stochastically forced, nonnormal linear dynamical systems. The method is applied to ERA-Interim and ERA-20C reanalysis data, demonstrating its ability to identify a number of well-known spatiotemporal coherent meteorological patterns and teleconnections, including the Madden–Julian oscillation (MJO), the quasi-biennial oscillation (QBO), and the El Niño–Southern Oscillation (ENSO) (i.e., a range of phenomena reoccurring with average periods ranging from months to many years). In addition to two-dimensional univariate analyses of surface data, we give examples of multivariate and three-dimensional meteorological patterns that illustrate how this technique can systematically identify coherent structures from different sets of data. The MATLAB code used to compute the results presented in this study, including the download scripts for the reanalysis data, is freely available online. },
doi = {10.1175/MWR-D-18-0337.1},
eprint = {https://doi.org/10.1175/MWR-D-18-0337.1},
url = {https://doi.org/10.1175/MWR-D-18-0337.1},
}
  • [PDF] Pickering, E. M., G. Rigas, D. Sipp, O. T. Schmidt, and T. Colonius. “Eddy viscosity for resolvent-based jet noise models.” 2019. 2454.
    [Bibtex] 
    @InProceedings{PickeringEtAl_2019_AIAA,
author = {Pickering, E. M. and Rigas, G. and Sipp, D. and Schmidt, O. T. and Colonius, T.},
title = {Eddy viscosity for resolvent-based jet noise models},
booktitle = {25th AIAA/CEAS Aeroacoustics Conference},
year = {2019},
pages = {2454},
}
  • [PDF] Nogueira, P. A., A. V. G. Cavalieri, O. T. Schmidt, P. Jordan, V. Jaunet, E. Pickering, G. Rigas, and T. Colonius. “Resolvent-based analysis of streaks in turbulent jets.” 2019. 2569.
    [Bibtex] 
    @InProceedings{NogueiraEtAl_2019_AIAA,
author = {Nogueira, P. A and Cavalieri, A. V. G. and Schmidt, O. T. and Jordan, P. and Jaunet, V. and Pickering, E. and Rigas, G. and Colonius, T.},
title = {Resolvent-based analysis of streaks in turbulent jets},
booktitle = {25th AIAA/CEAS Aeroacoustics Conference},
year = {2019},
pages = {2569},
}
  • [PDF] Rigas, G., E. M. Pickering, O. T. Schmidt, P. A. Nogueira, A. V. G. Cavalieri, G. A. Brès, and T. Colonius. “Streaks and coherent structures in jets from round and serrated nozzles.” 2019. 2597.
    [Bibtex] 
    @InProceedings{RigasEtAl_2019_AIAA,
author = {Rigas, G. and Pickering, E. M. and Schmidt, O. T. and Nogueira, P. A and Cavalieri,A. V. G. and Br{\`e}s, G. A. and Colonius, T.},
title = {Streaks and coherent structures in jets from round and serrated nozzles},
booktitle = {25th AIAA/CEAS Aeroacoustics Conference},
year = {2019},
pages = {2597},
}
  • [PDF] Towne, A., O. T. Schmidt, and G. A. Brès. “An investigation of the mach number dependence of trapped acoustic waves in turbulent jets.” 2019. 2546.
    [Bibtex] 
    @InProceedings{TowneSchmidtBres_2019_AIAA,
author = {Towne, A. and Schmidt, O. T. and Br{\`e}s, G. A.},
title = {An investigation of the Mach number dependence of trapped acoustic waves in turbulent jets},
booktitle = {25th AIAA/CEAS Aeroacoustics Conference},
year = {2019},
pages = {2546},
}
  • [PDF] Edgington-Mitchell, D. M., D. Duke, T. Wang, D. Harris, O. T. Schmidt, P. Jaunet V.and Jordan, and Aaron Towne. “Modulation of downstream-propagating waves in aeroacoustic resonance.” 2019. 2689.
    [Bibtex] 
    @InProceedings{EdgingtonEtAl_2019_AIAA,
author = {Edgington-Mitchell, D. M. and Duke, D. and Wang, T. and Harris, D. and Schmidt, O. T. and Jaunet, V.and Jordan, P. and Towne, Aaron},
title = {Modulation of downstream-propagating waves in aeroacoustic resonance},
booktitle = {25th AIAA/CEAS Aeroacoustics Conference},
year = {2019},
pages = {2689},
}
  • [PDF] Maia, I., P. Jordan, E. Martini, A. V. G. Cavalieri, A. Towne, L. Lesshafft, and O. T. Schmidt. “Real-time estimation in a turbulent jet using multiple-input-multiple-output transfer functions.” 2019. 2535.
    [Bibtex] 
    @InProceedings{MaiaEtAl_2019_AIAA,
author = {Maia, I. and Jordan, P. and Martini, E. and Cavalieri, A. V. G. and Towne, A. and Lesshafft, L. and Schmidt, O. T.},
title = {Real-Time Estimation in a Turbulent Jet Using Multiple-Input-Multiple-Output Transfer Functions},
booktitle = {25th AIAA/CEAS Aeroacoustics Conference},
year = {2019},
pages = {2535},
}
  • [PDF] [DOI] Schmidt, O. T. and P. J. Schmid. “A conditional space–time pod formalism for intermittent and rare events: example of acoustic bursts in turbulent jets.” Journal of fluid mechanics 867 (2019): R2.
    [Bibtex] 
    @Article{SchmidtSchmid_2019_JFMR,
author = {Schmidt, O. T. and Schmid, P. J.},
title = {A conditional space–time POD formalism for intermittent and rare events: example of acoustic bursts in turbulent jets},
journal = {Journal of Fluid Mechanics},
year = {2019},
volume = {867},
pages = {R2},
doi = {10.1017/jfm.2019.200},
file = {:SchmidtSchmid_2019_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}

2018

  • [PDF] [DOI] Jordan, P., V. Jaunet, A. Towne, A. V. G. Cavalieri, Colonius, O. T. Schmidt, and A. Agarwal. “Jet–flap interaction tones.” Journal of fluid mechanics 853 (2018): 333–358.
    [Bibtex] 
    @Article{JordanEtAl_2018_JFM,
author = {Jordan, P. and Jaunet, V. and Towne, A. and Cavalieri, A. V. G. and Colonius, and Schmidt, O. T. and Agarwal, A.},
title = {Jet–flap interaction tones},
journal = {Journal of Fluid Mechanics},
year = {2018},
volume = {853},
pages = {333–358},
doi = {10.1017/jfm.2018.566},
file = {:jordanetal_2018_jfm.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Brès, G., P. Jordan, M. Le Rallic, V. Jaunet, A. V. G. Cavalieri, A. Towne, S. Lele, T. Colonius, and O. T. Schmidt. “Importance of the nozzle-exit boundary-layer state in subsonic turbulent jets.” Journal of fluid mechanics 851 (2018): 83–124.
    [Bibtex] 
    @Article{BresEtAl_2018_JFM,
author = {Br{\`e}s, G. and Jordan, P. and Le Rallic, M. and Jaunet, V. and Cavalieri, A. V. G and Towne, A. and Lele, S. and Colonius, T. and Schmidt, O. T.},
title = {Importance of the nozzle-exit boundary-layer state in subsonic turbulent jets},
journal = {Journal of Fluid Mechanics},
year = {2018},
volume = {851},
pages = {83–124},
doi = {10.1017/jfm.2018.476},
file = {:BresEtAl_2018_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Towne, A., O. T. Schmidt, and T. Colonius. “Spectral proper orthogonal decomposition and its relationship to dynamic mode decomposition and resolvent analysis.” Journal of fluid mechanics 847 (2018): 821–867.
    [Bibtex] 
    @Article{TowneSchmidtColonius_2018_JFM,
author = {Towne, A. and Schmidt, O. T. and Colonius, T.},
title = {Spectral proper orthogonal decomposition and its relationship to dynamic mode decomposition and resolvent analysis},
journal = {Journal of Fluid Mechanics},
year = {2018},
volume = {847},
pages = {821–867},
doi = {10.1017/jfm.2018.283},
file = {:TowneSchmidtColonius_2018_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Schmidt, O. T., A. Towne, G. Rigas, T. Colonius, and G. A. Brès. “Spectral analysis of jet turbulence.” Journal of fluid mechanics 855 (2018): 953–982.
    [Bibtex] 
    @Article{SchmidtEtAl_2018_JFM,
author = {Schmidt, O. T. and Towne, A. and Rigas, G. and Colonius, T. and Br{\`e}s, G. A.},
title = {Spectral analysis of jet turbulence},
journal = {Journal of Fluid Mechanics},
year = {2018},
volume = {855},
pages = {953–982},
doi = {10.1017/jfm.2018.675},
file = {:SchmidtEtAl_2018_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Schmidt, O. T. and A. Towne. “An efficient streaming algorithm for spectral proper orthogonal decomposition.” Computer physics communications (2018).
    [Bibtex] 
    @Article{SchmidtTowne_2018_CPC,
author = {Schmidt, O. T. and Towne, A.},
title = {An efficient streaming algorithm for spectral proper orthogonal decomposition},
journal = {Computer Physics Communications},
year = {2018},
issn = {0010-4655},
abstract = {A streaming algorithm to compute the spectral proper orthogonal decomposition (SPOD) of stationary random processes is presented. As new data becomes available, an incremental update of the truncated eigenbasis of the estimated cross-spectral density (CSD) matrix is performed. The algorithm requires access to only one temporal snapshot of the data at a time and converges orthogonal sets of SPOD modes at discrete frequencies that are optimally ranked in terms of energy. We define measures of error and convergence, and demonstrate the algorithm’s performance on two datasets. The first example considers a high-fidelity numerical simulation of a turbulent jet, and the second example uses optical flow data obtained from high-speed camera recordings of a stepped spillway experiment. For both cases, the most energetic SPOD modes are reliably converged. The algorithm’s low memory requirement enables real-time deployment and allows for the convergence of second-order statistics from arbitrarily long streams of data. A MATLAB implementation of the algorithm along with a test database for the jet example, can be found in the Supplementary material.},
doi = {https://doi.org/10.1016/j.cpc.2018.11.009},
file = {:SchmidtTowne_2018_CPC.pdf:PDF},
keywords = {Proper orthogonal decomposition, Principal component analysis, Spectral analysis},
url = {http://www.sciencedirect.com/science/article/pii/S0010465518304016},}
  • [PDF] Antonialli, L. A., A. V. G. Cavalieri, O. T. Schmidt, T. Colonius, A. Towne, G. A. Brès, and P. Jordan. “Amplitude scaling of turbulent-jet wavepackets.” 24th aiaa/ceas aeroacoustics conference. 2018. .
    [Bibtex] 
    @InProceedings{AntonialliEtAl_2018_AIAA,
author = {L. A. Antonialli and A. V. G. Cavalieri and O. T. Schmidt and T. Colonius and A. Towne and G. A. Brès and P. Jordan},
title = {Amplitude scaling of turbulent-jet wavepackets},
journal = {24th AIAA/CEAS Aeroacoustics Conference},
year = {2018},
file = {:AntonialliEtAl_2018_AIAA.pdf:PDF},
}
  • [PDF] Brès, G. A., S. T. Bose, M. Emory, F. E. Ham, O. T. Schmidt, G. Rigas, and T. Colonius. “Large-eddy simulations of co-annular turbulent jet using a voronoi-based mesh generation framework.” 24th aiaa/ceas aeroacoustics conference. 2018. .
    [Bibtex] 
    @InProceedings{BresEtAl_2018_AIAA,
author = {G. A. Brès and S. T. Bose and M. Emory and F. E. Ham and O. T. Schmidt and G. Rigas and T. Colonius},
title = {Large-eddy simulations of co-annular turbulent jet using a Voronoi-based mesh generation framework},
journal = {24th AIAA/CEAS Aeroacoustics Conference},
year = {2018},
file = {:BresEtAl_2018_AIAA.pdf:PDF},
}

2017

  • [PDF] [DOI] Sasaki, K., A. V. G. Cavalieri, P. Jordan, O. T. Schmidt, T. Colonius, and G. A. Brès. “High-frequency wavepackets in turbulent jets.” Journal of fluid mechanics 830 (2017): R2.
    [Bibtex] 
    @Article{SasakiEtAl_2017_JFM,
author = {Sasaki, K. and Cavalieri, A. V. G. and Jordan, P. and Schmidt, O. T. and Colonius, T. and Br{\`e}s, G. A.},
title = {High-frequency wavepackets in turbulent jets},
journal = {Journal of Fluid Mechanics},
year = {2017},
volume = {830},
pages = {R2},
doi = {10.1017/jfm.2017.659},
file = {:SasakiEtAl_2017_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Schmidt, O. T., A. Towne, T. Colonius, A. V. G. Cavalieri, P. Jordan, and G. A. Brès. “Wavepackets and trapped acoustic modes in a turbulent jet: coherent structure eduction and global stability.” Journal of fluid mechanics 825 (2017): 1153-1181.
    [Bibtex] 
    @Article{SchmidtEtAl_2017_JFM,
author = {Schmidt, O. T. and Towne, A. and Colonius, T. and Cavalieri, A. V. G. and Jordan, P. and Br{\`e}s, G. A.},
title = {Wavepackets and trapped acoustic modes in a turbulent jet: coherent structure eduction and global stability},
journal = {Journal of Fluid Mechanics},
year = {2017},
volume = {825},
pages = {1153-1181},
doi = {10.1017/jfm.2017.407},
file = {:SchmidtEtAl_2017_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Taira, K., S. L. Brunton, S. Dawson, C. W. Rowley, T. Colonius, B. J. McKeon, O. T. Schmidt, S. Gordeyev, V. Theofilis, and L. S. Ukeiley. “Modal analysis of fluid flows: an overview.” Aiaa journal (2017).
    [Bibtex] 
    @Article{TairaEtAl_2017_AIAAJ,
author = {Taira, K. and Brunton, S. L. and Dawson, S. and Rowley, C. W. and Colonius, T. and McKeon, B. J. and Schmidt, O. T. and Gordeyev, S. and Theofilis, V. and Ukeiley, L. S.},
title = {Modal analysis of fluid flows: An overview},
journal = {AIAA Journal},
year = {2017},
doi = {https://doi.org/10.2514/1.J056060},
file = {:TairaEtAl_2017_AIAAJ.pdf:PDF},
}
  • [PDF] [DOI] Towne, A., A. V. G. Cavalieri, P. Jordan, T. Colonius, O. T. Schmidt, V. Jaunet, and G. A. Brès. “Acoustic resonance in the potential core of subsonic jets.” Journal of fluid mechanics 825 (2017): 1113-1152.
    [Bibtex] 
    @Article{TowneEtAl_2017_JFM,
author = {Towne, A. and Cavalieri, A. V. G. and Jordan, P. and Colonius, T. and Schmidt, O. T. and Jaunet, V. and Br{\`e}s, G. A.},
title = {Acoustic resonance in the potential core of subsonic jets},
journal = {Journal of Fluid Mechanics},
year = {2017},
volume = {825},
pages = {1113-1152},
doi = {10.1017/jfm.2017.346},
file = {:TowneEtAl_2017_JFM.pdf:PDF},
publisher = {Cambridge University Press},
}
  • [PDF] [DOI] Schmidt, O. T., T. Colonius, and G. A. Brès. “Wavepacket intermittency and its role in turbulent jet noise.” Aiaa science and technology forum and exposition. American Institute of Aeronautics and Astronautics (AIAA), 2017. .
    [Bibtex] 
    @InProceedings{SchmidtEtAl_2017_AIAA,
author = {O. T. Schmidt and T. Colonius and G. A. Br{\`e}s},
title = {Wavepacket intermittency and its role in turbulent jet noise},
journal = {AIAA Science and Technology Forum and Exposition},
year = {2017},
publisher = {American Institute of Aeronautics and Astronautics (AIAA)},
doi = {http://doi.org/10.2514/6.2016-3050},
file = {:SchmidtEtAl_2017_AIAA.pdf:PDF},
owner = {oschmidt},
timestamp = {2016.09.22},
}
  • [PDF] Schmidt, O. T., T. Colonius, and G. A. Brès. “Linear dynamics of large-scale structures in turbulent jets.” Tenth international symposium on turbulence and shear flow phenomena. 2017. .
    [Bibtex] 
    @InProceedings{SchmidtEtAl_2017_TSFP10,
author = {O. T. Schmidt and T. Colonius and G. A. Br{\`e}s},
title = {Linear dynamics of large-scale structures in turbulent jets},
journal = {Tenth International Symposium on Turbulence and Shear Flow Phenomena},
year = {2017},
file = {:SchmidtEtAl_2017_TSFP10.pdf:PDF},
}
  • [PDF] Rigas, G., O. T. Schmidt, T. Colonius, and G. A. Brès. “One-way navier-stokes and resolvent analysis for modeling coherent structures in a supersonic turbulent jet.” 23rd aiaa/ceas aeroacoustics conference. 2017. .
    [Bibtex] 
    @InProceedings{RigasEtAl_2017_AIAA,
author = {Rigas, G. and Schmidt, O. T. and Colonius, T. and Br{\`e}s, G. A.},
title = {One-Way Navier-Stokes and resolvent analysis for modeling coherent structures in a supersonic turbulent jet},
journal = {23rd AIAA/CEAS Aeroacoustics Conference},
year = {2017},
volume = {4046},
file = {:RigasEtAl_2017_AIAA.pdf:PDF},
}

2016

  • [PDF] [DOI] Staudenmeyer, J., O. T. Schmidt, and U. Rist. “On the influence of sommerfeld’s radiation boundary condition on the propagation direction of oblique modes in streamwise corner flow.” Journal of fluid mechanics 807 (2016): R3.
    [Bibtex] 
    @Article{StaudenmeyerSchmidtRist_2016_JFM,
Title = {On the influence of Sommerfeld's radiation boundary condition on the propagation direction of oblique modes in streamwise corner flow},
Author = {Staudenmeyer, J. and Schmidt, O. T. and Rist, U.},
Journal = {Journal of Fluid Mechanics},
Year = {2016},
Pages = {R3},
Volume = {807},
Doi = {10.1017/jfm.2016.642},
File = {:StaudenmeyerSchmidtRist_2016_JFM.pdf:PDF},
Publisher = {Cambridge University Press}
}
  • [PDF] [DOI] Brès, G. A., V. J., Le M. Rallic, P. Jordan, A. Towne, O. T. Schmidt, T. Colonius, A. V. G. Cavalieri, and S. K. Lele. “Large eddy simulation for jet noise: azimuthal decomposition and intermittency of the radiated sound.” 22nd aiaa/ceas aeroacoustics conference. American Institute of Aeronautics and Astronautics (AIAA), 2016. .
    [Bibtex] 
    @InProceedings{BresJaunetRallicEtAl_2016_AIAA,
author = {G. A. Br{\`e}s and V. J. and M. Le Rallic and P. Jordan and A. Towne and O. T. Schmidt and T. Colonius and A. V. G. Cavalieri and S. K. Lele},
title = {Large eddy simulation for jet noise: azimuthal decomposition and intermittency of the radiated sound},
journal = {22nd AIAA/CEAS Aeroacoustics Conference},
year = {2016},
publisher = {American Institute of Aeronautics and Astronautics (AIAA)},
doi = {http://doi.org/10.2514/6.2016-3050},
file = {:/Users/oschmidt/Documents/paper/BresJaunetRallicEtAl_2016_AIAA.pdf:PDF},
url = {http://colonius.caltech.edu/pdfs/BresJaunetRallicEtAl2016.pdf},
}
  • [PDF] [DOI] Cavalieri, A. V. G., K. Sasaki, P. Jordan, O. T. Schmidt, T. Colonius, and G. A. Brès. “High-frequency wavepackets in turbulent jets.” 22nd aiaa/ceas aeroacoustics conference. American Institute of Aeronautics and Astronautics (AIAA), 2016. .
    [Bibtex] 
    @InProceedings{CavalieriSasakiJordanEtAl_2016_AIAA,
author = {A. V. G. Cavalieri and K. Sasaki and P. Jordan and O. T. Schmidt and T. Colonius and G. A. Br{\`e}s},
title = {High-frequency wavepackets in turbulent jets},
journal = {22nd AIAA/CEAS Aeroacoustics Conference},
year = {2016},
publisher = {American Institute of Aeronautics and Astronautics (AIAA)},
doi = {http://doi.org/10.2514/6.2016-3056},
file = {:/Users/oschmidt/Documents/paper/CavalieriSasakiJordanEtAl_2016_AIAA.pdf:PDF},
url = {http://colonius.caltech.edu/pdfs/CavalieriSasakiJordanEtAl2016.pdf},
}
  • [PDF] [DOI] Jaunet, V., P. Jordan, A. V. G. Cavalieri, A. Towne, T. Colonius, O. T. Schmidt, and G. A. Brès. “Tonal dynamics and sound in subsonic turbulent jets.” 22nd aiaa/ceas aeroacoustics conference. American Institute of Aeronautics and Astronautics (AIAA), 2016. .
    [Bibtex] 
    @InProceedings{JaunetJordanCavalieriEtAl_2016_AIAA,
author = {V. Jaunet and P. Jordan and A. V. G. Cavalieri and A. Towne and T. Colonius and O. T. Schmidt and G. A. Br{\`e}s},
title = {Tonal dynamics and sound in subsonic turbulent jets},
journal = {22nd AIAA/CEAS Aeroacoustics Conference},
year = {2016},
publisher = {American Institute of Aeronautics and Astronautics (AIAA)},
doi = {http://doi.org/10.2514/6.2016-3016},
file = {:/Users/oschmidt/Documents/paper/JaunetJordanCavalieriEtAl_2016_AIAA.pdf:PDF},
url = {http://colonius.caltech.edu/pdfs/JaunetJordanCavalieriEtAl2016.pdf},
}
  • Schmidt, O. T., A. Towne, and T. Colonius. “Intrinsic and extrinsic linear dynamics of a high-reynolds number turbulent jet.” Euromech Colloquium 571 / IUTAM Symposium, 2016. .
    [Bibtex] 
    @InProceedings{SchmidtTowneColonius_2016_IUTAM,
author = {O. T. Schmidt and A. Towne and T. Colonius},
title = {Intrinsic and extrinsic linear dynamics of a high-Reynolds number turbulent jet},
year = {2016},
publisher = {Euromech Colloquium 571 / IUTAM Symposium},
owner = {oschmidt},
timestamp = {2016.09.22},
}
  • [PDF] [DOI] Schmidt, O. T., A. Towne, T. Colonius, P. Jordan, V. Jaunet, A. V. G. Cavalieri, and G. A. Brès. “Super- and multi-directive acoustic radiation by linear global modes of a turbulent jet.” 22nd aiaa/ceas aeroacoustics conference. American Institute of Aeronautics and Astronautics (AIAA), 2016. .
    [Bibtex] 
    @InProceedings{SchmidtTowneColoniusEtAl_2016_AIAA,
author = {O. T. Schmidt and A. Towne and T. Colonius and P. Jordan and V. Jaunet and A. V. G. Cavalieri and G. A. Br{\`e}s},
title = {Super- and multi-directive acoustic radiation by linear global modes of a turbulent jet},
journal = {22nd AIAA/CEAS Aeroacoustics Conference},
year = {2016},
publisher = {American Institute of Aeronautics and Astronautics (AIAA)},
doi = {http://doi.org/10.2514/6.2016-2808},
file = {:SchmidtTowneColoniusEtAl_2016_AIAA.pdf:PDF},
url = {http://colonius.caltech.edu/pdfs/SchmidtTowneColoniusEtAl2016.pdf},
}
  • [PDF] [DOI] Towne, A., A. V. G. Cavalieri, P. Jordan, T. Colonius, V. Jaunet, O. T. Schmidt, and G. A. Brès. “Trapped acoustic waves in the potential core of subsonic jets.” 22nd aiaa/ceas aeroacoustics conference. American Institute of Aeronautics and Astronautics (AIAA), 2016. .
    [Bibtex] 
    @InProceedings{TowneCavalieriJordanEtAl_2016_AIAA,
author = {A. Towne and A. V. G. Cavalieri and P. Jordan and T. Colonius and V. Jaunet and O. T. Schmidt and G. A. Br{\`e}s},
title = {Trapped acoustic waves in the potential core of subsonic jets},
journal = {22nd AIAA/CEAS Aeroacoustics Conference},
year = {2016},
publisher = {American Institute of Aeronautics and Astronautics (AIAA)},
doi = {http://doi.org/10.2514/6.2016-2809},
file = {:/Users/oschmidt/Documents/paper/TowneCavalieriJordanEtAl_2016_AIAA.pdf:PDF},
url = {http://colonius.caltech.edu/pdfs/TowneCavalieriJordanEtAl2016.pdf},
}

2015

  • [PDF] [DOI] Schmidt, O. T., S. M. Hosseini, Ulrich Rist, A. Hanifi, and D. S. Henningson. “Optimal wavepackets in streamwise corner flow.” Journal of fluid mechanics 766 (2015): 405–435.
    [Bibtex] 
    @Article{SchmidtEtAl_2015_JFM,
Title = {Optimal wavepackets in streamwise corner flow},
Author = {Schmidt, O. T. and Hosseini, S. M. and Rist, Ulrich and Hanifi, A. and Henningson, D. S.},
Journal = {Journal of Fluid Mechanics},
Year = {2015},
Pages = {405--435},
Volume = {766},
Doi = {10.1017/jfm.2015.18},
File = {:SchmidtEtAl_2015_JFM.pdf:PDF},
Publisher = {Cambridge Univ Press}
}

2014

  • [PDF] [DOI] Schmidt, O. T. and U. Rist. “Viscid–inviscid pseudo-resonance in streamwise corner flow.” Journal of fluid mechanics 743 (2014): 327–357.
    [Bibtex] 
    @Article{SchmidtRist_2014_JFM,
author = {Schmidt, O. T. and Rist, U.},
title = {Viscid--inviscid pseudo-resonance in streamwise corner flow},
journal = {Journal of Fluid Mechanics},
year = {2014},
volume = {743},
pages = {327--357},
doi = {10.1017/jfm.2014.31},
file = {:SchmidtRist_2014_JFM.pdf:PDF},
publisher = {Cambridge Univ Press},
}
  • [PDF] Schmidt, O. T. and U. Rist. “Numerical investigation of classical and bypass transition in streamwise corner-flow.” Iutam abcm symposium on laminar turbulent transition. 2014. .
    [Bibtex] 
    @InProceedings{SchmidtRist_2014_IUTAM,
author = {Schmidt, O. T. and Rist, U.},
title = {Numerical investigation of classical and bypass transition in streamwise corner-flow},
journal = {IUTAM ABCM Symposium on Laminar Turbulent Transition},
year = {2014},
file = {:SchmidtRist_2014_IUTAM.pdf:PDF},
owner = {oschmidt},
timestamp = {2016.09.22},
}

2013

  • [PDF] [DOI] Schmidt, O. T., B. Selent, and U. Rist. “Direct numerical simulation of boundary layer transition in streamwise corner-flow.” High performance computing in science and engineering (2013): 337-348.
    [Bibtex] 
    @Article{SchmidtRistSelent_2013_HPCSE,
author = {Schmidt, O. T. and Selent, B. and Rist, U.},
title = {Direct numerical simulation of boundary layer transition in streamwise corner-flow},
journal = {High Performance Computing in Science and Engineering},
year = {2013},
pages = {337-348},
doi = {10.1017/S0022112095003284},
file = {:SchmidtRistSelent_2013_HPCSE.pdf:PDF},
owner = {iagoschm},
publisher = {Cambridge Univ Press},
}

2011

  • [PDF] [DOI] Schmidt, O. T. and U. Rist. “Linear stability of compressible flow in a streamwise corner.” Journal of fluid mechanics 688 (2011): 569-590.
    [Bibtex] 
    @Article{SchmidtRist_2011_JFM,
Title = {Linear stability of compressible flow in a streamwise corner},
Author = {Schmidt, O. T. and Rist, U.},
Journal = {Journal of Fluid Mechanics},
Year = {2011},
Pages = {569-590},
Volume = {688},
Doi = {10.1017/jfm.2011.405},
File = {:./SchmidtRist_2011_JFM.pdf:PDF},
Publisher = {Cambridge Univ Press}
}
  • [PDF] Schmidt, O. T. and U. Rist. “Viscous and inviscid instabilities of supersonic flow in a streamwise corner.” 6th aiaa theoretical fluid mechanics conference. 2011. .
    [Bibtex] 
    @InProceedings{SchmidtRist_2011_AIAA,
author = {Schmidt, O. T. and Rist, U.},
title = {Viscous and inviscid instabilities of supersonic flow in a streamwise corner},
journal = {6th AIAA Theoretical Fluid Mechanics Conference},
year = {2011},
file = {:/Users/oschmidt/Documents/paper/SchmidtRist_2011_AIAA.pdf:PDF},
owner = {oschmidt},
timestamp = {2016.09.22},
}

2006

  • Wild, J. and O. T. Schmidt. “Prediction of attachment line transition for a high-lift wing based on two-dimensional flow calculations with RANS-solver.” New results in numerical and experimental fluid mechanics 5 (2006): 200-207.
    [Bibtex] 
    @Article{WildSchmidt_NRNEFM_2006,
Title = {Prediction of attachment line transition for a high-lift wing based on two-dimensional flow calculations with {RANS}-solver},
Author = {Wild, J. and Schmidt, O. T.},
Journal = {New Results in Numerical and Experimental Fluid Mechanics},
Year = {2006},
Pages = {200-207},
Volume = {5},
Owner = {iagoschm}
}