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Hybrid spectral-particle method for the turbulent transport of a passive scalar

J.-B. Lagaert, G. Balarac, G.-H. Cottet
2014 Journal of Computational Physics  
This paper describes a novel hybrid method, combining a spectral and a particle method, to simulate the turbulent transport of a passive scalar.  ...  In particular, theoretical predictions of universal scaling in forced homogeneous turbulence are recovered for a wide range of Schmidt numbers for large, intermediate and small scales of the scalar.  ...  The authors thankfully acknowledge the hospitality of the Center for Turbulence Research, NASA-Ames and Stanford University, where part of this work has been done during the Summer Program 2012.  ... 
doi:10.1016/ fatcat:hh4hrkkgjnc6volnfnyywivwvy

A mass-conserving advection scheme for offline simulation of scalar transport in coastal ocean models

P.A. Gillibrand, M. Herzfeld
2016 Ocean Modelling  
Citation for published version (APA): Gillibrand, P., & Herzfeld, M. (2016). A mass-conserving advection scheme for offline simulation of scalar transport in coastal ocean models.  ...  A suite of horizontal mixing, turbulence closure, For each test, the transport model was run three times using, in turn, the FFSL scheme, the 379 traditional semi-Lagrangian advection scheme and the semi-Lagrangian  ...  c) RMS error for the transport model simulation with a semi-Lagrangian advection 945 scheme; (d) RMS error for the transport model with a semi-Lagrangian scheme plus global filling. 946 The total tracer  ... 
doi:10.1016/j.ocemod.2016.02.008 fatcat:u6jzttzpqfgzfovwgf3f3bnwsa

Lagrangian statistics and flow topology in forced two-dimensional turbulence

B. Kadoch, D. del-Castillo-Negrete, W. J. T. Bos, K. Schneider
2011 Physical Review E  
In contrast to the freely decaying turbulence case, the conditional pdfs of the Lagrangian acceleration in forced turbulence show a comparable level of intermittency in the periodic and the bounded domains  ...  We follow a Lagrangian approach and obtain the statistics by tracking large ensembles of passively advected tracers.  ...  Moisy for fruitful discussions in the framework of the GDR turbulence, and G. Keetels is acknowledged for discussions about the forcing term.  ... 
doi:10.1103/physreve.83.036314 pmid:21517594 fatcat:o2mdrnbnu5hnjeirg4h3f6sgee

Mixing in Turbulent Flows: An Overview of Physics and Modelling

Jacek Pozorski, Marta Wacławczyk
2020 Processes  
In this paper, we present an overview of such flows (with no particular emphasis on combustion, however) and we recall the major types of micro-mixing models developed within the statistical approaches  ...  Turbulent flows featuring additional scalar fields, such as chemical species or temperature, are common in environmental and industrial applications.  ...  An attempt to improve over the undesirable behaviour of the IEM, while keeping the scalar values bounded, was the binomial sampling model of Valiño and Dopazo [76] that belongs to the class of stochastic  ... 
doi:10.3390/pr8111379 fatcat:w2t3u6psk5a3lcokccewjeaz24

Scalar excursions in large-eddy simulations

Georgios Matheou, Paul E. Dimotakis
2016 Journal of Computational Physics  
7 The range of values of scalar fields in turbulent flows is bounded by their boundary values, 8 for passive scalars, and by a combination of boundary values, reaction rates, phase changes, 9 etc., for  ...  The current investigation focuses on the local conservation of passive 10 scalar concentration fields and the ability of the large-eddy simulation (LES) method to observe 11 the boundedness of passive  ...  Blanquart, 2014: An improved bounded semi-lagrangian scheme for 876 the turbulent transport of passive scalars. J. Comput. Phys., 272, 1-22. 877 Voelkl, T., D. I. Pullin, and D. C.  ... 
doi:10.1016/ fatcat:anhtkapmejf4hl3l7jhvcb7vou

The application of flux-form semi-Lagrangian transport scheme in a spectral atmosphere model

Xiaocong Wang, Yimin Liu, Guoxiong Wu, Shian-Jiann Lin, Qing Bao
2012 Advances in Atmospheric Sciences  
A flux-form semi-Lagrangian transport scheme (FFSL) was implemented in a spectral atmospheric GCM developed and used at IAP/LASG.  ...  Importantly, FFSL can automatically maintain the positive definition of the transported tracers, which was an underlying problem in the previous spectral composite method (SCM).  ...  This study was jointly supported by the Chinese Academy of Science Strategic Priority Research Program (Grant No.  ... 
doi:10.1007/s00376-012-2039-2 fatcat:jsogsrmpjffgzoztzthptutsj4

Statistical Models of Large Scale Turbulent Flow

J. J. H. Brouwers
2016 Flow Turbulence and Combustion  
The equations enable the derivation of descriptions for transport by turbulent fluctuations of conserved scalars, momentum, kinetic energy, pressure and energy dissipation as a function of the derivative  ...  The Langevin and diffusion equations for statistical velocity and displacement of marked fluid particles are formulated for turbulent flow at large Reynolds number for which Lagrangian Kolmogorov K-41  ...  An old and still widely used approach is to average the Navier-Stokes equations and to introduce a semi-empirical description for turbulent momentum and scalar transport.  ... 
doi:10.1007/s10494-015-9701-6 fatcat:qyrxflx3bfavdpi6lkirpklqje

Simplified models for turbulent diffusion: Theory, numerical modelling, and physical phenomena

Andrew J. Majda, Peter R. Kramer
1999 Physics reports  
usion of a passive scalar "eld are developed here with an emphasis on the symbiotic interaction between rigorous mathematical theory (including exact solutions), physical intuition, and numerical simulations  ...  PII: S 0 3 7 0 -1 5 7 3 ( 9 8 ) 0 0 0 8 3 -0 Abstract Several simple mathematical models for the turbulent di!  ...  usion, Marco Avellaneda, for his explicit and implicit contributions to this review. The authors also thank David Horntrop and Richard McLaughlin for their help with the "gures for Sections 2 and 6.  ... 
doi:10.1016/s0370-1573(98)00083-0 fatcat:puis2cnparcanbifseokux5fry

Quasi-Monotone Advection Schemes Based on Explicit Locally Adaptive Dissipation

Alexander F. Shchepetkin, James C. McWilliams
1998 Monthly Weather Review  
This is done for both advection of vorticity and passive scalar.  ...  The authors develop and test computational methods for advection of a scalar field that also include a minimal dissipation of its variance in order to preclude the formation of false extrema.  ...  This research was supported by the National Science Foundation Grant ECS 9217394 and Office of Naval Research Grant ONR-N00014-95-1-0316. APPENDIX A  ... 
doi:10.1175/1520-0493(1998)126<1541:qmasbo>;2 fatcat:udc2alyhhfbyrd5dxiawuijiqa

A Review of Vortex Methods and Their Applications: From Creation to Recent Advances

Chloé Mimeau, Iraj Mortazavi
2021 Fluids  
This review paper presents an overview of Vortex Methods for flow simulation and their different sub-approaches, from their creation to the present.  ...  The present review aims to describe the Vortex methods by following their chronological evolution and provides for each step of their development the mathematical framework, the strengths and limits as  ...  Scalars Transport Scalar advection problems involve the coupling of the Navier-Stokes equations with an advection-diffusion equation for the scalar transported at the flow velocity.  ... 
doi:10.3390/fluids6020068 fatcat:unqqtr7vcjea3nz7hjkxzv2gxm

Quantification of mesoscale transport across the boundaries of the free troposphere: a new method and applications to ozone

F. Gheusi, J.-P. Cammas, F. Cousin, C. Mari, P. Mascart
2004 Atmospheric Chemistry and Physics Discussions  
Such an air-mass can be characterized by e.g., a criterion on the initial and final values of the turbulent kinetic energy of the air-parcels.  ...  A new Lagrangian method is proposed to quantify the transport of ozone -or any other atmospheric constituent -by objectively-defined air-masses.  ...  Improvements are also expected on the Lagrangian retrieval technique that serves to define the transporting air-mass (in particular regarding the interpolation scheme that should ensure mass-conservation  ... 
doi:10.5194/acpd-4-8103-2004 fatcat:mgwhvkxdbba7hnt5ojjaxp7zz4

A PDF micromixing model of dispersion for atmospheric flow. Part I: development of the model, application to homogeneous turbulence and to neutral boundary layer

M. Cassiani, P. Franzese, U. Giostra
2005 Atmospheric Environment  
A Lagrangian stochastic (LS) probability density function (PDF) model has been developed to study statistics and PDF of concentration generated by continuous releases of passive substances from point and  ...  Turbulent dispersion is modelled using an LS model; molecular diffusivity is simulated by an interaction by exchange with the conditional mean (IECM) model.  ...  Acknowledgements We acknowledge Dr Brian Sawford for helpful discussions in the early stage of this work and for sending us the preprints of his works.  ... 
doi:10.1016/j.atmosenv.2004.11.020 fatcat:33c4fkmncfbclgw4mxa3xsmwsy

Fluctuations of a passive scalar in a turbulent mixing layer

Antonio Attili, Fabrizio Bisetti
2013 Physical Review E  
In this paper, a detailed statistical analysis of fluctuations of a passive scalar in the fully developed region of a turbulent mixing layer from a direct numerical simulation is presented.  ...  Conversely, intermittency saturation is not observed for the spanwise increments and the relative scaling exponents agree with recent results for homogeneous isotropic turbulence with mean scalar gradient  ...  An additional transport equation for a passive scalar with Schmidt number equal to 0.7 is also solved.  ... 
doi:10.1103/physreve.88.033013 pmid:24125350 fatcat:rbizjcudwvfxhmf6pcbaoz3mui

Turbulent mixing in a tubular reactor: Assessment of an FDF/LES approach

E. van Vliet, J. J. Derksen, H. E. A. van den Akker
2005 AIChE Journal  
The aim of the present research was to investigate the feasibility of a probability density function (PDF) methodology combined with a large eddy simulation (LES) for turbulent reactive mixing in industrial  ...  diffusivity in the transition region of the laminar jet to the the turbulent wake of the injector.  ...  The N s dimensional FDF transport equation (N s being the number of scalar components) is most naturally solved within a Lagrangian Monte Carlo (MC) framework.  ... 
doi:10.1002/aic.10365 fatcat:cqlwm7kj7jh3zptktz6pddio2e

Mixing by stirring: optimizing shapes and strategies [article]

Maximilian F. Eggl, Peter J. Schmid
2021 arXiv   pre-print
We propose a PDE-constrained optimization approach to address the problem of mixing enhancement for binary fluids.  ...  Within a gradient-based framework, we target the stirring strategy as well as the cross-sectional shape of the stirrers to achieve improved mixedness over a given time horizon and within a prescribed energy  ...  The process can be simulated by solving the fluid equations of motion, augmented by a transport equation for a passive scalar that identifies the binary fluid.  ... 
arXiv:2108.07064v1 fatcat:qltfofbubzhshlxd2wnz2iuge4
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