The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform
Anthony T. Patera - One of the best experts on this subject based on the ideXlab platform.
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a space time variational approach to Hydrodynamic Stability theory
Proceedings of The Royal Society A: Mathematical Physical and Engineering Sciences, 2013Co-Authors: Masayuki Yano, Anthony T. PateraAbstract:We present a Hydrodynamic Stability theory for incompressible viscous fluid flows based on a space-time variational formulation and associated generalized singular value decomposition of the (linearized) Navier-Stokes equations. We first introduce a linear framework applicable to a wide variety of stationary or time-dependent base flows: we consider arbitrary disturbances in both the initial condition and the dynamics measured in a “data” space-time norm; the theory provides a rigorous, sharp (realizable), and eciently computed bound for the velocity perturbation measured in a “solution” spacetime norm. We next present a generalization of the linear framework in which the disturbances and perturbation are now measured in respective selected space-time seminorms; the semi-norm theory permits rigorous and sharp quantification of, for example, the growth of initial disturbances or functional outputs. We then develop a (BrezziRappaz-Raviart) nonlinear theory which provides, for disturbances which satisfy a certain (rather stringent) amplitude condition, rigorous finite-amplitude bounds for the velocity and output perturbations. Finally, we demonstrate the application of our linear and nonlinear Hydrodynamic Stability theory to unsteady moderate Reynolds-number flow in an eddy-promoter channel.
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A space–time variational approach to Hydrodynamic Stability theory
Proceedings of the Royal Society A: Mathematical Physical and Engineering Sciences, 2013Co-Authors: Masayuki Yano, Anthony T. PateraAbstract:We present a Hydrodynamic Stability theory for incompressible viscous fluid flows based on a space-time variational formulation and associated generalized singular value decomposition of the (linearized) Navier-Stokes equations. We first introduce a linear framework applicable to a wide variety of stationary or time-dependent base flows: we consider arbitrary disturbances in both the initial condition and the dynamics measured in a “data” space-time norm; the theory provides a rigorous, sharp (realizable), and eciently computed bound for the velocity perturbation measured in a “solution” spacetime norm. We next present a generalization of the linear framework in which the disturbances and perturbation are now measured in respective selected space-time seminorms; the semi-norm theory permits rigorous and sharp quantification of, for example, the growth of initial disturbances or functional outputs. We then develop a (BrezziRappaz-Raviart) nonlinear theory which provides, for disturbances which satisfy a certain (rather stringent) amplitude condition, rigorous finite-amplitude bounds for the velocity and output perturbations. Finally, we demonstrate the application of our linear and nonlinear Hydrodynamic Stability theory to unsteady moderate Reynolds-number flow in an eddy-promoter channel.
Masayuki Yano - One of the best experts on this subject based on the ideXlab platform.
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a space time variational approach to Hydrodynamic Stability theory
Proceedings of The Royal Society A: Mathematical Physical and Engineering Sciences, 2013Co-Authors: Masayuki Yano, Anthony T. PateraAbstract:We present a Hydrodynamic Stability theory for incompressible viscous fluid flows based on a space-time variational formulation and associated generalized singular value decomposition of the (linearized) Navier-Stokes equations. We first introduce a linear framework applicable to a wide variety of stationary or time-dependent base flows: we consider arbitrary disturbances in both the initial condition and the dynamics measured in a “data” space-time norm; the theory provides a rigorous, sharp (realizable), and eciently computed bound for the velocity perturbation measured in a “solution” spacetime norm. We next present a generalization of the linear framework in which the disturbances and perturbation are now measured in respective selected space-time seminorms; the semi-norm theory permits rigorous and sharp quantification of, for example, the growth of initial disturbances or functional outputs. We then develop a (BrezziRappaz-Raviart) nonlinear theory which provides, for disturbances which satisfy a certain (rather stringent) amplitude condition, rigorous finite-amplitude bounds for the velocity and output perturbations. Finally, we demonstrate the application of our linear and nonlinear Hydrodynamic Stability theory to unsteady moderate Reynolds-number flow in an eddy-promoter channel.
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A space–time variational approach to Hydrodynamic Stability theory
Proceedings of the Royal Society A: Mathematical Physical and Engineering Sciences, 2013Co-Authors: Masayuki Yano, Anthony T. PateraAbstract:We present a Hydrodynamic Stability theory for incompressible viscous fluid flows based on a space-time variational formulation and associated generalized singular value decomposition of the (linearized) Navier-Stokes equations. We first introduce a linear framework applicable to a wide variety of stationary or time-dependent base flows: we consider arbitrary disturbances in both the initial condition and the dynamics measured in a “data” space-time norm; the theory provides a rigorous, sharp (realizable), and eciently computed bound for the velocity perturbation measured in a “solution” spacetime norm. We next present a generalization of the linear framework in which the disturbances and perturbation are now measured in respective selected space-time seminorms; the semi-norm theory permits rigorous and sharp quantification of, for example, the growth of initial disturbances or functional outputs. We then develop a (BrezziRappaz-Raviart) nonlinear theory which provides, for disturbances which satisfy a certain (rather stringent) amplitude condition, rigorous finite-amplitude bounds for the velocity and output perturbations. Finally, we demonstrate the application of our linear and nonlinear Hydrodynamic Stability theory to unsteady moderate Reynolds-number flow in an eddy-promoter channel.
M. M. Marinak - One of the best experts on this subject based on the ideXlab platform.
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national ignition facility targets driven at high radiation temperature ignition Hydrodynamic Stability and laser plasma interactions
Physics of Plasmas, 2004Co-Authors: D E Hinkel, S. W. Haan, A. B. Langdon, C.h. Still, T R Dittrich, M. M. MarinakAbstract:A target design driven indirectly to ignition at a radiation temperature of 350 eV for the National Ignition Facility (NIF) is reported in integrated radiation-Hydrodynamic simulations which detail the necessary specifications to achieve ignition and burn. The target is further analyzed to determine its Hydrodynamic Stability as well as its vulnerability to laser–plasma interactions. This target shows enhanced Hydrodynamic Stability over targets previously designed at lower radiation temperatures [S. W. Haan, S. M. Pollaine, J. D. Lindl et al., Phys. Plasmas 2, 2480 (1995); W. J. Krauser, N. M. Hoffman, D. C. Wilson et al., ibid.3, 2084 (1996); D. C. Wilson, P. A. Bradley, N. M. Hoffman et al., ibid.5, 1953 (1998); P. A. Bradley and D. C. Wilson, ibid.6, 4293 (1999)]. To control laser–plasma instabilities, both polarization and temporal smoothing of the spatially smoothed NIF laser beams is necessary. Analyses of laser scatter in target blow-off at peak power demonstrate saturation in both the 300 and 350...
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National Ignition Facility targets driven at high radiation temperature: Ignition, Hydrodynamic Stability, and laser–plasma interactions
Physics of Plasmas, 2004Co-Authors: Denise Hinkel, S. W. Haan, A. B. Langdon, Tom Dittrich, C.h. Still, M. M. MarinakAbstract:A target design driven indirectly to ignition at a radiation temperature of 350 eV for the National Ignition Facility (NIF) is reported in integrated radiation-Hydrodynamic simulations which detail the necessary specifications to achieve ignition and burn. The target is further analyzed to determine its Hydrodynamic Stability as well as its vulnerability to laser–plasma interactions. This target shows enhanced Hydrodynamic Stability over targets previously designed at lower radiation temperatures [S. W. Haan, S. M. Pollaine, J. D. Lindl et al., Phys. Plasmas 2, 2480 (1995); W. J. Krauser, N. M. Hoffman, D. C. Wilson et al., ibid.3, 2084 (1996); D. C. Wilson, P. A. Bradley, N. M. Hoffman et al., ibid.5, 1953 (1998); P. A. Bradley and D. C. Wilson, ibid.6, 4293 (1999)]. To control laser–plasma instabilities, both polarization and temporal smoothing of the spatially smoothed NIF laser beams is necessary. Analyses of laser scatter in target blow-off at peak power demonstrate saturation in both the 300 and 350...
Bamin Khomami - One of the best experts on this subject based on the ideXlab platform.
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A new approach for studying the Hydrodynamic Stability of fluids with microstructure
Physics of Fluids, 2001Co-Authors: Madan Somasi, Bamin KhomamiAbstract:A new methodology for studying the Stability of fluids with microstructure has been developed. This technique relies on combining continuum based conservation equations and stochastic simulation techniques to determine the Hydrodynamic Stability of flows under consideration. To illustrate the capability of the method, the Stability of viscoelastic Taylor–Couette flow has been examined.
S. W. Haan - One of the best experts on this subject based on the ideXlab platform.
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national ignition facility targets driven at high radiation temperature ignition Hydrodynamic Stability and laser plasma interactions
Physics of Plasmas, 2004Co-Authors: D E Hinkel, S. W. Haan, A. B. Langdon, C.h. Still, T R Dittrich, M. M. MarinakAbstract:A target design driven indirectly to ignition at a radiation temperature of 350 eV for the National Ignition Facility (NIF) is reported in integrated radiation-Hydrodynamic simulations which detail the necessary specifications to achieve ignition and burn. The target is further analyzed to determine its Hydrodynamic Stability as well as its vulnerability to laser–plasma interactions. This target shows enhanced Hydrodynamic Stability over targets previously designed at lower radiation temperatures [S. W. Haan, S. M. Pollaine, J. D. Lindl et al., Phys. Plasmas 2, 2480 (1995); W. J. Krauser, N. M. Hoffman, D. C. Wilson et al., ibid.3, 2084 (1996); D. C. Wilson, P. A. Bradley, N. M. Hoffman et al., ibid.5, 1953 (1998); P. A. Bradley and D. C. Wilson, ibid.6, 4293 (1999)]. To control laser–plasma instabilities, both polarization and temporal smoothing of the spatially smoothed NIF laser beams is necessary. Analyses of laser scatter in target blow-off at peak power demonstrate saturation in both the 300 and 350...
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National Ignition Facility targets driven at high radiation temperature: Ignition, Hydrodynamic Stability, and laser–plasma interactions
Physics of Plasmas, 2004Co-Authors: Denise Hinkel, S. W. Haan, A. B. Langdon, Tom Dittrich, C.h. Still, M. M. MarinakAbstract:A target design driven indirectly to ignition at a radiation temperature of 350 eV for the National Ignition Facility (NIF) is reported in integrated radiation-Hydrodynamic simulations which detail the necessary specifications to achieve ignition and burn. The target is further analyzed to determine its Hydrodynamic Stability as well as its vulnerability to laser–plasma interactions. This target shows enhanced Hydrodynamic Stability over targets previously designed at lower radiation temperatures [S. W. Haan, S. M. Pollaine, J. D. Lindl et al., Phys. Plasmas 2, 2480 (1995); W. J. Krauser, N. M. Hoffman, D. C. Wilson et al., ibid.3, 2084 (1996); D. C. Wilson, P. A. Bradley, N. M. Hoffman et al., ibid.5, 1953 (1998); P. A. Bradley and D. C. Wilson, ibid.6, 4293 (1999)]. To control laser–plasma instabilities, both polarization and temporal smoothing of the spatially smoothed NIF laser beams is necessary. Analyses of laser scatter in target blow-off at peak power demonstrate saturation in both the 300 and 350...
