Turbulence, large eddy

To analy2e premixed turbulent flames theoretically, two processes should be considered (/) the effects of combustion on the turbulence, and (2) the effects of turbulence on the average chemical reaction rates. In a turbulent flame, the peak time-averaged reaction rate can be orders of magnitude smaller than the corresponding rates in a laminar flame. The reason for this is the existence of turbulence-induced fluctuations in composition, temperature, density, and heat release rate within the flame, which are caused by large eddy stmctures and wrinkled laminar flame fronts. 

With turbulent flow, shear stress also results from the behavior of transient random eddies, including large-scale eddies which decay to small eddies or fluctuations. The scale of the large eddies depends on equipment size. On the other hand, the scale of small eddies, which dissipate energy primarily through viscous shear, is almost independent of agitator and tank size. 

Another detailed method of determining pressures is computational fluid dynamics (CFD), which uses a numerical solution of simplified equations of motion over a dense grid of points around the building. Murakami et al. and Zhoy and Stathopoulos found less agreement with computational fluid dynamics methods using the k-e turbulence model typically used in current commercial codes. More advanced turbulence models such as large eddy simulation were more successful but much more costly. ... 

David.son, L, Large eddy simulation A dynamic one-equation subgrid model for three-dimensional recirculating flow. In llth Int. Symp. on Turbulent Shear Flow, vol. 3, pp. 26.1-26.6, Grenoble, 1997. 

L. Duchamp de Lageneste and H. Pitsch 2001, Progress in the large eddy simulation of premixed and partially premixed turbulent combustion, in Center for Turbulence Research (CTR, Stanford) Annual Research Brief. 

The ability to resolve the dissipation structures allows a more detailed understanding of the interactions between turbulent flows and flame chemistry. This information on spectra, length scales, and the structure of small-scale turbulence in flames is also relevant to computational combustion models. For example, information on the locally measured values of the Batchelor scale and the dissipation-layer thickness can be used to design grids for large-eddy simulation (LES) or evaluate the relative resolution of LES resulfs. There is also the potential to use high-resolution dissipation measurements to evaluate subgrid-scale models for LES. 

Pitsch, H. and Steiner, H., Scalar mixing and dissipation rate in large-eddy simulations of non-premixed turbulent combustion, Proc. Combust. Inst., 28, 41, 2000. 

Colin, O., et al., A thickened flame model for large-eddy simulations of turbulent premixed combustion. Phi/s. Fluids, 2000.12(7) 1843-1863. 

Moreau, M., B. Bedat, and O. Simonin, From Euler-Lagrange to Euler-Euler large eddy simulation approaches for gas-particle turbulent flows, in ASME Fluids Engineering Summer Conference, Houston. 2005, ASME FED. 

Riber, E., et al.. Towards large eddy simulation of non-homogeneous particle laden turbulent gas flows using Euler-Euler approach, in Eleventh Workshop on Two-Phase Flow Predictions. 2005, Merseburg, Germany. 

Celik, L, 1. Yavuz, and A. Smirnov, Large eddy simulations of in-cylinder turbulence for internal combustion engines A review. Int. J. Eng Res., 2001.2(2) 119-148. 

The most efficient turbulent eddies for bubble breakup are eddies of the same size as the bubbles. Large eddies will merely move the bubbles and smaller eddies do not have sufficient energy to break up the bubbles. Assuming that the most efficient eddies to break up fluid particles are eddies of the same size as the bubble, that is, A. 2d, gives the required turbulent energy dissipation... 

Large eddy simulations explicitly resolves the inherently unsteady character of the turbulent flow in a stirred tank into account, including the periodic phenomena associated with the motion of the impeller and their interaction with... 

Van Vliet, E., Derksen, J. J., and Van den Akker, H. E. A., Modelling of Parallel Competitive Reactions in Isotropic Homogeneous Turbulence Using a Filtered Density Function Approach for Large Eddy Simulations . Proc. PVP01 3rd Int. Symp. on Comput. Techn. for Fluid/Thermal/Chemical Systems with Industrial Appl., Atlanta, GE, USA (2001). 

Chigiefl211 found that turbulence in a liquid jet has important disturbing influences throughout the liquid flow. At the liquid surface, turbulent velocity fluctuations directly cause protuberances and roughness that result in direct stripping by surrounding air flow. Large eddy structures in the air flow penetrate into the liquid and... 

Akselvoll, K. and P. Moin (1996). Large eddy simulation of turbulent confined coannular jets. 

Branley, N. and W. P. Jones (2001). Large eddy simulation of a turbulent non-premixed flame. Combustion and Flame 127, 1914-1934. 

Bushe, W. K. and H. Steiner (1999). Conditional moment closure for large eddy simulation of nonpremixed turbulent reacting flows. Physics of Fluids 11, 1896-1906. 

Calmet, I. and J. Magnaudet (1997). Large-eddy simulation of high-Schmidt number mass transfer in a turbulent channel flow. Physics of Fluids 9,438 155. 

Colucci, R J., F. A. Jaberi, P. Givi, and S. B. Pope (1998). Filtered density function for large eddy simulation of turbulent reacting flows. Physics of Fluids 10,499-515. 

Erratum A large-eddy simulation scheme for turbulent reacting flows [Phys. Fluids A 5, 1282 (1993)]. Physics of Fluids 6, 1621. 

Hughes, T. J. R., A. A. Oberai, and L. Mazzei (2001a). Large eddy simulation of turbulent channel flows by the variational multiscale method. Physics of Fluids 13, 1784-1799. 

Pitsch, H. and H. Steiner (2000). Large-eddy simulation of a turbulent piloted methane/air diffusion flame (Sandia flame D). Physics of Fluids 12, 2541-2554. 

Vedula, P., P. K. Yeung, and R. O. Fox (2001). Dynamics of scalar dissipation in isotropic turbulence A numerical and modeling study. Journal of Fluid Mechanics 433, 29-60. Verman, B., B. Geurts, and H. Kuertan (1994). Realizability conditions for the turbulent stress tensor in large-eddy simulations. Journal of Fluid Mechanics 278, 351-362. Vervisch, L. (1991). Prise en compte d effets de cinetique chimique dans lesflammes de diffusion turbulente par Tapproche fonction densite de probabilite. Ph. D. thesis, Universite de Rouen, France. 

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