Numerical simulation of the high Reynolds number slit nozzle gas–particle jet using subgrid-scale coupling large eddy simulation

Yuu, Shinichi; Ueno, Takashi; Umekage, Toshihiko

doi:10.1016/s0009-2509(01)00050-1

Cited by 53 publications

(18 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Yuu et al [15] has modeled turbulent viscosity coefficient of subgrid-scale turbulence caused by subgrid-scale fluctuations using LES in which the effect of particle oscillations on gas turbulence has been taken into account. The turbulent viscosity of gases is as follows:…”

Section: Continuity and Momentum Equations For Gas Phasementioning

confidence: 99%

Numerical study on the cluster flow behavior in the riser of circulating fluidized beds

Liu

Huilin

2009

Chemical Engineering Journal

View full text Add to dashboard Cite

Section: Continuity and Momentum Equations For Gas Phasementioning

confidence: 99%

Numerical study on the cluster flow behavior in the riser of circulating fluidized beds

Liu

Huilin

2009

Chemical Engineering Journal

View full text Add to dashboard Cite

“…Because the SGS modelling in these LES was confined to the gas phase, SGS-flux models for incompressible SP flow could be used; these LES used constant-coefficient or dynamic-coefficient Smagorinsky (see Smagorinksy 1993) SGS-flux modelling, which is based on gradient diffusion with an eddy viscosity coefficient. The Smagorinsky model was also used in the TP LES of solid particles by Yuu, Ueno & Umekage (2001); in their incompressible flow, the particles were assumed monodisperse, and the SGS-flux of drop number density appearing in the FSTs was also modelled using the gradient-diffusion concept.…”

Section: Introductionmentioning

confidence: 99%

Consistent large-eddy simulation of a temporal mixing layer laden with evaporating drops. Part 2. A posteriori modelling

2005

View full text Add to dashboard Cite

Large-eddy simulation (LES) is conducted of a three-dimensional temporal mixing layer whose lower stream is initially laden with liquid drops which may evaporate during the simulation. The gas-phase equations are written in an Eulerian frame for two perfect gas species (carrier gas and vapour emanating from the drops), while the liquid-phase equations are written in a Lagrangian frame. The effect of drop evaporation on the gas phase is considered through mass, species, momentum and energy source terms. The drop evolution is modelled using physical drops, or using computational drops to represent the physical drops. Simulations are performed using various LES models previously assessed on a database obtained from direct numerical simulations (DNS). These LES models are for: (i) the subgrid-scale (SGS) fluxes and (ii) the filtered source terms (FSTs) based on computational drops. The LES, which are compared to filtered-and-coarsened (FC) DNS results at the coarser LES grid, are conducted with 64 times fewer grid points than the DNS, and up to 64 times fewer computational than physical drops. It is found that both constantcoefficient and dynamic Smagorinsky SGS-flux models, though numerically stable, are overly dissipative and damp generated small-resolved-scale (SRS) turbulent structures. Although the global growth and mixing predictions of LES using Smagorinsky models are in good agreement with the FC-DNS, the spatial distributions of the drops differ significantly. In contrast, the constant-coefficient scale-similarity model and the dynamic gradient model perform well in predicting most flow features, with the latter model having the advantage of not requiring a priori calibration of the model coefficient. The ability of the dynamic models to determine the model coefficient during LES is found to be essential since the constant-coefficient gradient model, although more accurate than the Smagorinsky model, is not consistently numerically stable despite using DNS-calibrated coefficients. With accurate SGS-flux models, namely scale-similarity and dynamic gradient, the FST model allows up to a 32-fold reduction in computational drops compared to the number of physical drops, without degradation of accuracy; a 64-fold reduction leads to a slight decrease in accuracy.

show abstract

“…For spatially evolving flows, the gas-solid non-reactive isothermal jet has been investigated extensively with numerical and experimental techniques [17], with a focus on particle effects on gas-flow turbulence, i.e., turbulence modulation. With the addition of chemical reaction and phase change, the vast majority of studies are concerned with spray combustion, which has applications in modern gas turbine engines and Diesel engines.…”

Section: Introductionmentioning

confidence: 99%

Large-Eddy Simulation of Interactions Between a Reacting Jet and Evaporating Droplets

Xia

Luo

Kumar

2007

Flow Turbulence Combust

View full text Add to dashboard Cite

Large-eddy simulation of a turbulent reactive jet with and without evaporating droplets is performed to investigate the interactions among turbulence, combustion, heat transfer and evaporation. A hybrid Eulerian-Lagrangian approach is used for the gas-liquid flow system. Arrhenius-type finite-rate chemistry is employed for the chemical reaction. To capture the highly local interactions, dynamic procedures are used for all the subgrid-scale models, except that the filtered reaction rate is modelled by a scale similarity model. Various representative cases with different initial droplet sizes (St 0 ) and mass loading ratios (MLR) have been simulated, along with a case without droplets. It is found that compared with the bigger, slow responding droplets (St 0 =16), smaller droplets (St 0 =1) are more efficient in suppressing combustion due to their preferential concentration in the reaction zones. The peak temperature and intensity of temperature fluctuations are found to be reduced in all the droplet cases, to a varying extent depending on the droplet properties. Detailed analysis on the contributions of respective terms in a transport equation for gridscale kinetic energy (GSKE) shows that the droplet evaporation effect on GSKE is small, while the droplet momentum effect depends on St 0 . When the MLR is sufficiently high, the bigger (St 0 =16) droplets can have profound influence on GSKE, and consequently on the formation and evolution of large-scale flow structures. On the other hand, the turbulence level is found to be lower in the droplet cases than in the pure flame case, due to the dissipative droplet dynamic effect.

show abstract

Numerical simulation of the high Reynolds number slit nozzle gas–particle jet using subgrid-scale coupling large eddy simulation

Cited by 53 publications

References 13 publications

Numerical study on the cluster flow behavior in the riser of circulating fluidized beds

Numerical study on the cluster flow behavior in the riser of circulating fluidized beds

Consistent large-eddy simulation of a temporal mixing layer laden with evaporating drops. Part 2. A posteriori modelling

Large-Eddy Simulation of Interactions Between a Reacting Jet and Evaporating Droplets

Contact Info

Product

Resources

About