A stochastic perturbation method to generate inflow turbulence in largeeddy simulation models: Application to neutrally stratified atmospheric boundary layers
Abstract
Despite the variety of existing methods, efficient generation of turbulent inflow conditions for largeeddy simulation (LES) models remains a challenging and active research area. Herein, we extend our previous research on the cell perturbation method, which uses a novel stochastic approach based upon finite amplitude perturbations of the potential temperature field applied within a region near the inflow boundaries of the LES domain [MuñozEsparza et al., “Bridging the transition from mesoscale to microscale turbulence in numerical weather prediction models,” BoundaryLayer Meteorol., 153, 409–440 (2014)]. The objective was twofold: (i) to identify the governing parameters of the method and their optimum values and (ii) to generalize the results over a broad range of atmospheric largescale forcing conditions, U{sub g} = 5 − 25 m s{sup −1}, where U{sub g} is the geostrophic wind. We identified the perturbation Eckert number, Ec=U{sub g}{sup 2}/ρc{sub p}θ{sup ~}{sub pm}, to be the parameter governing the flow transition to turbulence in neutrally stratified boundary layers. Here, θ{sup ~}{sub pm} is the maximum perturbation amplitude applied, c{sub p} is the specific heat capacity at constant pressure, and ρ is the density. The optimal Eckert number was found for nonlinear perturbations allowed by Ec ≈ 0.16, which instigatemore »
 Authors:
 Earth and Environmental Sciences Division (EES16), Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States)
 National Center for Atmospheric Research, P.O. Box 3000, Boulder, Colorado 80307 (United States)
 von Karman Institute for Fluid Dynamics, 72 Chaussée de Waterloo, B1640 RhodeStGenèse (Belgium)
 Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)
 Publication Date:
 OSTI Identifier:
 22403216
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Fluids (1994); Journal Volume: 27; Journal Issue: 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; BOUNDARY LAYERS; DISTURBANCES; EQUILIBRIUM; KINETIC ENERGY; LARGEEDDY SIMULATION; MATHEMATICAL SOLUTIONS; NONLINEAR PROBLEMS; PERTURBATION THEORY; REYNOLDS NUMBER; SHEAR; SPECIFIC HEAT; STOCHASTIC PROCESSES; THREEDIMENSIONAL CALCULATIONS; TURBULENCE; VORTICES
Citation Formats
MuñozEsparza, D., Kosović, B., Beeck, J. van, and Mirocha, J. A stochastic perturbation method to generate inflow turbulence in largeeddy simulation models: Application to neutrally stratified atmospheric boundary layers. United States: N. p., 2015.
Web. doi:10.1063/1.4913572.
MuñozEsparza, D., Kosović, B., Beeck, J. van, & Mirocha, J. A stochastic perturbation method to generate inflow turbulence in largeeddy simulation models: Application to neutrally stratified atmospheric boundary layers. United States. doi:10.1063/1.4913572.
MuñozEsparza, D., Kosović, B., Beeck, J. van, and Mirocha, J. 2015.
"A stochastic perturbation method to generate inflow turbulence in largeeddy simulation models: Application to neutrally stratified atmospheric boundary layers". United States.
doi:10.1063/1.4913572.
@article{osti_22403216,
title = {A stochastic perturbation method to generate inflow turbulence in largeeddy simulation models: Application to neutrally stratified atmospheric boundary layers},
author = {MuñozEsparza, D. and Kosović, B. and Beeck, J. van and Mirocha, J.},
abstractNote = {Despite the variety of existing methods, efficient generation of turbulent inflow conditions for largeeddy simulation (LES) models remains a challenging and active research area. Herein, we extend our previous research on the cell perturbation method, which uses a novel stochastic approach based upon finite amplitude perturbations of the potential temperature field applied within a region near the inflow boundaries of the LES domain [MuñozEsparza et al., “Bridging the transition from mesoscale to microscale turbulence in numerical weather prediction models,” BoundaryLayer Meteorol., 153, 409–440 (2014)]. The objective was twofold: (i) to identify the governing parameters of the method and their optimum values and (ii) to generalize the results over a broad range of atmospheric largescale forcing conditions, U{sub g} = 5 − 25 m s{sup −1}, where U{sub g} is the geostrophic wind. We identified the perturbation Eckert number, Ec=U{sub g}{sup 2}/ρc{sub p}θ{sup ~}{sub pm}, to be the parameter governing the flow transition to turbulence in neutrally stratified boundary layers. Here, θ{sup ~}{sub pm} is the maximum perturbation amplitude applied, c{sub p} is the specific heat capacity at constant pressure, and ρ is the density. The optimal Eckert number was found for nonlinear perturbations allowed by Ec ≈ 0.16, which instigate formation of hairpinlike vortices that most rapidly transition to a developed turbulent state. Larger Ec numbers (linear smallamplitude perturbations) result in streaky structures requiring larger fetches to reach the quasiequilibrium solution, while smaller Ec numbers lead to buoyancy dominated perturbations exhibiting difficulties for hairpinlike vortices to emerge. Cell perturbations with wavelengths within the inertial range of threedimensional turbulence achieved identical quasiequilibrium values of resolved turbulent kinetic energy, q, and Reynoldsshear stress, . In contrast, largescale perturbations acting at the production range exhibited reduced levels of , due to the formation of coherent streamwise structures, while q was maintained, requiring larger fetches for the turbulent solution to stabilize. Additionally, the cell perturbation method was compared to a synthetic turbulence generator. The proposed stochastic approach provided at least the same efficiency in developing realistic turbulence, while accelerating the formation of largescales associated with production of turbulent kinetic energy. Also, it is computationally inexpensive and does not require any turbulent information.},
doi = {10.1063/1.4913572},
journal = {Physics of Fluids (1994)},
number = 3,
volume = 27,
place = {United States},
year = 2015,
month = 3
}

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