New insights into large eddy simulation

Boris, J. P.; Grinstein, Fernando F.; Oran, Elaine S.; Kolbe, R. L.

doi:10.1016/0169-5983(92)90023-p

Cited by 867 publications

(400 citation statements)

References 82 publications

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“…The temporal integration is performed by an explicit 5-stage Runge Kutta method with second-order accuracy as well. The LES formulation is based on the monotone integrated LES (MILES) approach [18] modeling the impact of the subgrid scales by numerical dissipation. A detailed description of the fundamental LES solver is given by Meinke et al [19] and its convincing solution quality for fully turbulent sub-and supersonic §ows is discussed by Alkishriwi et al [20] and El-Askary et al [21].…”

Section: Flow Solvermentioning

confidence: 99%

Experimental and numerical investigation of the turbulent wake flow of a generic space launcher configuration

Statnikov

Saile

Meiss

et al. 2015

Progress in Flight Physics – Volume 7

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The turbulent wake of a generic space launcher at cold hypersonic freestream conditions is investigated experimentally and numerically to gain detailed insight into the intricate base §ow phenomena of space vehicles at upper stages of the §ight trajectory. The experiments are done at Ma ∞ = 6 and Re D = 1.7 · 10 6 m −1 by the German Aerospace Center (DLR) and the corresponding computations are performed by the Institute of Aerodynamics Aachen using a zonal Reynolds-averaged Navier Stokes / Large-Eddy Simulation (RANS/LES) approach. Two di¨erent aft-body geometries consisting of a blunt base and an attached cylindrical nozzle dummy are considered. It is found that the wind tunnel model support attached to the upper side of the main body has a nonnegligible impact on the wake along the whole circumference, albeit on the opposite side, the e¨ects are minimal compared to an axisymmetric con¦guration. In the blunt-base case, the turbulent supersonic boundary layer undergoes a strong aftexpansion on the model shoulder leading to the formation of a con¦ned low-pressure (p/p ∞ ≈ 0.2) recirculation region. Adding a nozzle dummy causes the shear layer to reattach on the its wall at x/D ∼ 0.6 and the base pressure level to increase (p/p ∞ ≈ 0.25) compared to the blunt-base case. For both con¦gurations, the pressure §uctuations on the base wall feature dominant frequencies at Sr D ≈ 0.05 and Sr D ≈ 0.2 0.27, but are of small amplitudes (p rms /p ∞ = 0.02 0.025) compared to the main body boundary layer. For the nozzle dummy con¦guration, when moving downstream along the nozzle extension, the wall pressure is increasingly in §uenced by the reattaching shear layer and the periodic low-frequency behavior

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Section: Flow Solvermentioning

confidence: 99%

Experimental and numerical investigation of the turbulent wake flow of a generic space launcher configuration

Statnikov

Saile

Meiss

et al. 2015

Progress in Flight Physics – Volume 7

View full text Add to dashboard Cite

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“…3b. The potential-core region is evident by the zero shear stress at x/S = 0, 16. At x/S = 30, the laminar slot boundary layer has undergone transition which is indicated by the negative peak shear stress close to the wall.…”

Section: Zero-pressure Gradient Con¦guration (Case I)mentioning

confidence: 92%

“…The temporal integration is done by a second-order ¦ve-stage low-storage Runge Kutta method. The nonresolved subgrid scales are implicitly modeled using the multiple integrated LES ansatz [16]. The viscosity is evaluated by a power law µ/µ 0 = (T /T 0 ) 0.72 where T 0 denotes the stagnation temperature.…”

Section: Methodsmentioning

confidence: 99%

Large-eddy simulation of high mach number film cooling with shock-wave interaction

Konôpka

Meinke

Schröder

2013

Progress in Flight Physics

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The impact of shock waves on supersonic cooling ¦lms is studied using large-eddy simulations (LES). A laminar cooling ¦lm is injected through a slot at a Mach number Ma i = 1.8 into a fully turbulent boundary layer at a freestream Mach number Ma ∞ = 2.44. The cooling ¦lm is disturbed by oblique shock waves at de §ection angles of 5 • and 8 • at two downstream positions of the slot. At shock impingement close to the slot, i. e., within the potential-core region, at a §ow de §ection of 5 • , a cooling e¨ectiveness decrease of 33% occurs downstream of the separation bubble compared to a con¦guration without shock impingement. If the same shock impinges further downstream upon the boundary-layer region, the decrease is only 17%. The stronger 8 degree shock wave at the further downstream impingement position leads to a maximum decrease of 33%.

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“…We rely on the MILES approach to mimic the high-wavenumber end of the inertial subrange (e.g., Boris et al 1992;Porter & Woodward 1994), but see also Garnier et al (1999) and Domaradzki (2010) for a discussion of limitations.…”

Section: Methodsmentioning

confidence: 99%

Supersonic turbulence in 3D isothermal flow collision

Folini

Walder

Favre

2014

A&A

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Large scale supersonic bulk flows are present in a wide range of astrophysical objects, from O-star winds to molecular clouds, galactic sheets, accretion, or γ-ray bursts. Associated flow collisions shape observable properties and internal physics alike. Our goal is to shed light on the interplay between large scale aspects of such collision zones and the characteristics of the compressible turbulence they harbor. Our model setup is as simple as can be: 3D hydrodynamical simulations of two head-on colliding, isothermal, and homogeneous flows with identical upstream (subscript u) flow parameters and Mach numbers 2 < M u < 43. The turbulence in the collision zone is driven by the upstream flows, whose kinetic energy is partly dissipated and spatially modulated by the shocks confining the zone. Numerical results are in line with expectations from self-similarity arguments. The spatial scale of modulation grows with the collision zone. The fraction of energy dissipated at the confining shocks decreases with increasing M u . The mean density is ρ m ≈ 20ρ u , independent of M u . The root mean square Mach number is M rms ≈ 0.25M u . Deviations toward weaker turbulence are found as the collision zone thickens and for small M u . The density probability function is not log-normal. The turbulence is inhomogeneous, weaker in the center of the zone than close to the confining shocks. It is also anisotropic: transverse to the upstream flows M rms is always subsonic. We argue that uniform, head-on colliding flows generally disfavor turbulence that is at the same time isothermal, supersonic, and isotropic. The anisotropy carries over to other quantities like the density variance -Mach number relation. Line-of-sight effects thus exist. Structure functions differ depending on whether they are computed along a line-of-sight perpendicular or parallel to the upstream flow. Turbulence characteristics generally deviate markedly from those found for uniformly driven, supersonic, isothermal turbulence in 3D periodic box simulations. We suggest that this should be kept in mind when interpreting turbulence characteristics derived from observations. Our simulations show that even a simple model setup results in a richly structured interaction zone. The robustness of our findings toward more realistic setups remains to be tested.

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New insights into large eddy simulation

Cited by 867 publications

References 82 publications

Experimental and numerical investigation of the turbulent wake flow of a generic space launcher configuration

Experimental and numerical investigation of the turbulent wake flow of a generic space launcher configuration

Large-eddy simulation of high mach number film cooling with shock-wave interaction

Supersonic turbulence in 3D isothermal flow collision

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