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Sébastien Deck - One of the best experts on this subject based on the ideXlab platform.
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On the Convection Velocity of Wall-Bounded Turbulence Resolved by ZDES Mode III at $$Re_\theta = 13 000$$
Progress in Hybrid RANS-LES Modelling, 2018Co-Authors: Nicolas Renard, Sébastien DeckAbstract:WMLES simulations of a flat-plate zero-pressure-gradient boundary layer are done with the Zonal Detached Eddy Simulation Mode III technique over a wide range of Reynolds numbers \(3\,150 \le Re_\theta \le 14\,000\). A WMLES field is compared with the WRLES interpolated onto the WMLES mesh. Two interface heights are considered, \(y_\text {interface} = 0.1 \delta \) and \(y^+_\text {interface} = 3.9 \sqrt{Re_\tau }\). The prediction and resolved fraction of mean skin friction is discussed, as well as remaining issues, especially in the logarithmic layer. An excess of high-wavelength streamwise Velocity fluctuations is observed below the RANS/LES interface with \(y^+_\text {interface} = 3.9 \sqrt{Re_\tau }\), and studied by a spectral Convection Velocity analysis, leading to the suggestion that it may be a footprint of coherent structures located further away from the wall.
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On the Convection Velocity of wall-bounded turbulence resolved by ZDES mode III at Re θ = 13 000
2018Co-Authors: Nicolas Renard, Sébastien DeckAbstract:WMLES simulations of a flat-plate zero-pressure-gradient boundary layer are done with the Zonal Detached Eddy Simulation Mode III technique over a wide range of Reynolds numbers 3150≤Reθ≤14000. A WMLES field is compared with the WRLES interpolated onto the WMLES mesh. Two interface heights are considered, yinterface=0.1δ and y+interface=3.9√Reτ. The prediction and resolved fraction of mean skin friction is discussed, as well as remaining issues, especially in the logarithmic layer. An excess of high-wavelength streamwise Velocity fluctuations is observed below the RANS/LES interface with y+interface=3.9√Reτ, and studied by a spectral Convection Velocity analysis, leading to the suggestion that it may be a footprint of coherent structures located further away from the wall.ZONAL DETACHED EDDY SIMULATION, REYNOLDS NUMBERS, RANS/LES INTERFACE, Convection Velocity,
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On the Convection Velocity of wall-bounded turbulence resolved by ZDES mode III at Re θ = 13 000
2016Co-Authors: Nicolas Renard, Sébastien DeckAbstract:The Convection Velocity of resolved streamwise Velocity fluctuations by a ZDES mode III WMLES simulation of high-Reynolds-number ZPG flat plate turbulent boundary layer is spectrally assessed. The physical nature of the fluctuations is then discussed.
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Spectral assessment of the turbulent Convection Velocity in a spatially developing flat plate turbulent boundary layer at Reynolds numbers up to Re Thêta = 13000
2016Co-Authors: Nicolas Renard, Sébastien Deck, Pierre SagautAbstract:A method inspired by del Álamo and Jiménez, J Fluid Mech 640:5–26, 2009, [7] is derived to assess the wavelength-dependent Convection Velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at Re_thêta=13000 for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise Velocity and of its local spatial derivative. The resulting global Convection Velocity has a least-squares interpretation and is easily related to the wavelength-dependent Convection Velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from del Álamo and Jiménez, J Fluid Mech 640:5–26, 2009, [7]. The results reveal some similarities between the Convection of the superstructures, the hairpin packets, and the near-wall structures. The Convection Velocity of the superstructures is isolated by restricting the global Convection Velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent Convection Velocity. The results are consistent with a classical correlation-based evaluation.
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Spectral Assessment of the Turbulent Convection Velocity in a Spatially Developing Flat Plate Turbulent Boundary Layer at Reynolds Number Re_\theta = 13\,000
Progress in Wall Turbulence 2, 2015Co-Authors: Nicolas Renard, Sébastien Deck, Pierre SagautAbstract:A method inspired by del Alamo and Jimenez, J Fluid Mech 640:5–26, 2009, [7] is derived to assess the wavelength-dependent Convection Velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at \(Re_\theta = 13\,000\) for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise Velocity and of its local spatial derivative. The resulting global Convection Velocity has a least-squares interpretation and is easily related to the wavelength-dependent Convection Velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from del Alamo and Jimenez, J Fluid Mech 640:5–26, 2009, [7]. The results reveal some similarities between the Convection of the superstructures, the hairpin packets, and the near-wall structures. The Convection Velocity of the superstructures is isolated by restricting the global Convection Velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent Convection Velocity. The results are consistent with a classical correlation-based evaluation.
Nicolas Renard - One of the best experts on this subject based on the ideXlab platform.
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On the Convection Velocity of Wall-Bounded Turbulence Resolved by ZDES Mode III at $$Re_\theta = 13 000$$
Progress in Hybrid RANS-LES Modelling, 2018Co-Authors: Nicolas Renard, Sébastien DeckAbstract:WMLES simulations of a flat-plate zero-pressure-gradient boundary layer are done with the Zonal Detached Eddy Simulation Mode III technique over a wide range of Reynolds numbers \(3\,150 \le Re_\theta \le 14\,000\). A WMLES field is compared with the WRLES interpolated onto the WMLES mesh. Two interface heights are considered, \(y_\text {interface} = 0.1 \delta \) and \(y^+_\text {interface} = 3.9 \sqrt{Re_\tau }\). The prediction and resolved fraction of mean skin friction is discussed, as well as remaining issues, especially in the logarithmic layer. An excess of high-wavelength streamwise Velocity fluctuations is observed below the RANS/LES interface with \(y^+_\text {interface} = 3.9 \sqrt{Re_\tau }\), and studied by a spectral Convection Velocity analysis, leading to the suggestion that it may be a footprint of coherent structures located further away from the wall.
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On the Convection Velocity of wall-bounded turbulence resolved by ZDES mode III at Re θ = 13 000
2018Co-Authors: Nicolas Renard, Sébastien DeckAbstract:WMLES simulations of a flat-plate zero-pressure-gradient boundary layer are done with the Zonal Detached Eddy Simulation Mode III technique over a wide range of Reynolds numbers 3150≤Reθ≤14000. A WMLES field is compared with the WRLES interpolated onto the WMLES mesh. Two interface heights are considered, yinterface=0.1δ and y+interface=3.9√Reτ. The prediction and resolved fraction of mean skin friction is discussed, as well as remaining issues, especially in the logarithmic layer. An excess of high-wavelength streamwise Velocity fluctuations is observed below the RANS/LES interface with y+interface=3.9√Reτ, and studied by a spectral Convection Velocity analysis, leading to the suggestion that it may be a footprint of coherent structures located further away from the wall.ZONAL DETACHED EDDY SIMULATION, REYNOLDS NUMBERS, RANS/LES INTERFACE, Convection Velocity,
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On the Convection Velocity of wall-bounded turbulence resolved by ZDES mode III at Re θ = 13 000
2016Co-Authors: Nicolas Renard, Sébastien DeckAbstract:The Convection Velocity of resolved streamwise Velocity fluctuations by a ZDES mode III WMLES simulation of high-Reynolds-number ZPG flat plate turbulent boundary layer is spectrally assessed. The physical nature of the fluctuations is then discussed.
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Spectral assessment of the turbulent Convection Velocity in a spatially developing flat plate turbulent boundary layer at Reynolds numbers up to Re Thêta = 13000
2016Co-Authors: Nicolas Renard, Sébastien Deck, Pierre SagautAbstract:A method inspired by del Álamo and Jiménez, J Fluid Mech 640:5–26, 2009, [7] is derived to assess the wavelength-dependent Convection Velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at Re_thêta=13000 for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise Velocity and of its local spatial derivative. The resulting global Convection Velocity has a least-squares interpretation and is easily related to the wavelength-dependent Convection Velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from del Álamo and Jiménez, J Fluid Mech 640:5–26, 2009, [7]. The results reveal some similarities between the Convection of the superstructures, the hairpin packets, and the near-wall structures. The Convection Velocity of the superstructures is isolated by restricting the global Convection Velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent Convection Velocity. The results are consistent with a classical correlation-based evaluation.
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Spectral Assessment of the Turbulent Convection Velocity in a Spatially Developing Flat Plate Turbulent Boundary Layer at Reynolds Number Re_\theta = 13\,000
Progress in Wall Turbulence 2, 2015Co-Authors: Nicolas Renard, Sébastien Deck, Pierre SagautAbstract:A method inspired by del Alamo and Jimenez, J Fluid Mech 640:5–26, 2009, [7] is derived to assess the wavelength-dependent Convection Velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at \(Re_\theta = 13\,000\) for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise Velocity and of its local spatial derivative. The resulting global Convection Velocity has a least-squares interpretation and is easily related to the wavelength-dependent Convection Velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from del Alamo and Jimenez, J Fluid Mech 640:5–26, 2009, [7]. The results reveal some similarities between the Convection of the superstructures, the hairpin packets, and the near-wall structures. The Convection Velocity of the superstructures is isolated by restricting the global Convection Velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent Convection Velocity. The results are consistent with a classical correlation-based evaluation.
V. G. Pimshtein - One of the best experts on this subject based on the ideXlab platform.
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Disturbance Convection Velocity in turbulent jets under aeroacoustic excitation
Journal of Applied Mechanics and Technical Physics, 2007Co-Authors: V. G. PimshteinAbstract:The Velocity of propagation of toroidal and oblique vortices formed in subsonic and supersonic turbulent jets under longitudinal internal and transverse external excitation by finite-amplitude saw-tooth acoustic waves is studied experimentally. It is demonstrated that the Convection Velocity of vortices is not constant, and the character of its variation depends on the vortex shape.
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Occurrence and Development of Vortices in Turbulent Jets under the Effect of Sawtooth Sound Waves of Finite Amplitude
Journal of Engineering Physics and Thermophysics, 2002Co-Authors: V. G. PimshteinAbstract:Consideration is given to the formation of vortices in turbulent jets under the effect of sawtooth sound waves of finite amplitude in the case of internal longitudinal acoustic action. The Convection Velocity and the rate of rise of the disturbances are determined. It is shown that the transverse dimensions of the disturbances increase linearly on the initial portion of the flow.
Pierre Sagaut - One of the best experts on this subject based on the ideXlab platform.
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Spectral assessment of the turbulent Convection Velocity in a spatially developing flat plate turbulent boundary layer at Reynolds numbers up to Re Thêta = 13000
2016Co-Authors: Nicolas Renard, Sébastien Deck, Pierre SagautAbstract:A method inspired by del Álamo and Jiménez, J Fluid Mech 640:5–26, 2009, [7] is derived to assess the wavelength-dependent Convection Velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at Re_thêta=13000 for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise Velocity and of its local spatial derivative. The resulting global Convection Velocity has a least-squares interpretation and is easily related to the wavelength-dependent Convection Velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from del Álamo and Jiménez, J Fluid Mech 640:5–26, 2009, [7]. The results reveal some similarities between the Convection of the superstructures, the hairpin packets, and the near-wall structures. The Convection Velocity of the superstructures is isolated by restricting the global Convection Velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent Convection Velocity. The results are consistent with a classical correlation-based evaluation.
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Spectral Assessment of the Turbulent Convection Velocity in a Spatially Developing Flat Plate Turbulent Boundary Layer at Reynolds Number Re_\theta = 13\,000
Progress in Wall Turbulence 2, 2015Co-Authors: Nicolas Renard, Sébastien Deck, Pierre SagautAbstract:A method inspired by del Alamo and Jimenez, J Fluid Mech 640:5–26, 2009, [7] is derived to assess the wavelength-dependent Convection Velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at \(Re_\theta = 13\,000\) for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise Velocity and of its local spatial derivative. The resulting global Convection Velocity has a least-squares interpretation and is easily related to the wavelength-dependent Convection Velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from del Alamo and Jimenez, J Fluid Mech 640:5–26, 2009, [7]. The results reveal some similarities between the Convection of the superstructures, the hairpin packets, and the near-wall structures. The Convection Velocity of the superstructures is isolated by restricting the global Convection Velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent Convection Velocity. The results are consistent with a classical correlation-based evaluation.
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Spectral assessment of the turbulent Convection Velocity in a spatially developing flat plate turbulent boundary layer at Reynolds numbers up to Re θ = 13000
2014Co-Authors: Nicolas Renard, Sébastien Deck, Pierre SagautAbstract:A method inspired by del Alamo et al. [1] is derived to assess the wavelength-dependent Convection Velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at Retheta = 13 000 for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise Velocity and of its local spatial derivative. The resulting global Convection Velocity has a least-squares interpretation and is easily related to the wavelength-dependent Convection Velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from [1]. The results reveal some similarities between the Convection of the superstructures, the hairpin packets and the near-wall structures. The Convection Velocity of the superstructures is isolated by restricting the global Convection Velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent Convection Velocity. The results are consistent with a classical correlation-based evaluation.1. del Alamo, J.C., Jimenez, J.: Estimation of turbulent Convection velocities and corrections to Taylor’s approximation. Journal of Fluid Mechanics 640, 5–26 (2009)
E. Pogrebnyak - One of the best experts on this subject based on the ideXlab platform.
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Convection Velocity of Temperature Fluctuations in a Turbulent Flume
Journal of Heat Transfer, 2004Co-Authors: Gad Hetsroni, Iztok Tiselj, R. Bergant, Albert Mosyak, E. PogrebnyakAbstract:A numerical investigation of the temperature field in a turbulent flume is presented. We consider the effect of the Prandtl number on the Convection Velocity of temperature fluctuations in a turbulent boundary layer, and focus also on the effect of the Prandtl number on the connection between the Velocity and the temperature fluctuations