Journal ArticleDOI
Expanded analogy between Boltzmann kinetic theory of fluids and turbulence
TLDR
In this article, the effects of turbulent fluctuations have a striking resemblance to those of microscale (thermal) fluctuations in laminar flows, even to higher order in the Knudsen number.Abstract:
We demonstrate that the effects of turbulent fluctuations have a striking resemblance to those of microscale (thermal) fluctuations in laminar flows, even to higher order in the Knudsen number. This suggests that there may be a good basis for understanding turbulence in terms of Boltzmann kinetic theory. If so, turbulence may be better described in terms of ‘mixing times’ rather than the more classical ‘mixing lengths’. Comparisons are made to Reynolds-stress turbulence models.read more
Citations
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Proceedings ArticleDOI
Experimental validation of ducted low-speed cooling fan noise prediction methods including broadband scattering
Julien Christophe,Korcan Kucukcoskun,Dominic Lallier-Daniels,Marlène Sanjosé,Stéphane Moreau +4 more
Proceedings ArticleDOI
Experimental and Numerical Investigation of Installed Ducted Propulsor Aeroacoustics
TL;DR: In this paper , a low-solidity electric ducted fan propulsor was tested in the VA Tech Anechoic Wind Tunnel in three installation configurations: isolated, close-coupled to an upstream airfoil, and planar boundary layer-ingesting.
Proceedings ArticleDOI
Data-driven Empirical Wall pressure Spectrum Models for Fan Noise Prediction
Shubham Shubham,Saurabh Pargal,Stéphane Moreau,Richard D. Sandberg,Junlin Yuan,Abhijit Kushari,Marlène Sanjosé +6 more
TL;DR: In this article , the authors evaluated six empirically based wall pressure spectra models for low-cost broadband noise prediction for rotating machines, focusing on the rotor self-noise caused by the scattering of turbulent eddies at the trailing edge of the rotor blades.
Proceedings ArticleDOI
A Gas-Kinetic Scheme For The Simulation Of Compressible Turbulent Flows
TL;DR: In this paper, a gas-kinetic scheme is modified to simulate turbulent flow; the turbulent relaxation time is deduced from assumed turbulent quantities, and a measure of rarefaction is introduced, as the ratio between unresolved and resolved time scales of motion.
Journal ArticleDOI
Visualisation of Roof Bar Noise Sources through the Use of Acoustic Beamforming and Computational Aeroacoustics
Oliver Smith,Nicholas Oettle +1 more
TL;DR: In this article , the authors combined acoustic beamforming in a full-scale aero-acoustic wind tunnel and the use of a Lattice Boltzmann Method CFD code to characterise the aeroacoustic performance of a roof bar design when fitted to a production vehicle.
References
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Journal ArticleDOI
The numerical computation of turbulent flows
Brian Launder,D. B. Spalding +1 more
TL;DR: In this paper, the authors present a review of the applicability and applicability of numerical predictions of turbulent flow, and advocate that computational economy, range of applicability, and physical realism are best served by turbulence models in which the magnitudes of two turbulence quantities, the turbulence kinetic energy k and its dissipation rate ϵ, are calculated from transport equations solved simultaneously with those governing the mean flow behaviour.
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Journal ArticleDOI
Development of turbulence models for shear flows by a double expansion technique
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Journal ArticleDOI
The Mathematical Theory of Non-Uniform Gases
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