Large Eddy simulation of a droplet laden turbulent mixing layer

Jones, W.P.; Lyra, S.; Marquis, A. J.

doi:10.1016/j.ijheatfluidflow.2009.10.001

Cited by 8 publications

(14 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The spray model, equations (4)- (12) has previously been applied to the simulation of dispersion in a water droplet laden mixing layer, [17,31], to evaporating acetone and kerosene sprays, [18,32] and to an axisymmetric combustion chamber, [33,34].…”

Section: Modelling Of Droplet Dispersion and Evaporationmentioning

confidence: 99%

Large-eddy simulation of spray combustion in a gas turbine combustor

Jones

Marquis

Vogiatzaki

2014

Combustion and Flame

Self Cite

119

View full text Add to dashboard Cite

This is the accepted version of the paper.This version of the publication may differ from the final published version. Permanent repository link AbstractThe paper describes the results of a comprehensive study of turbulent mixing, fuel spray dispersion and evaporation and combustion in a gas-turbine combustor geometry (the DLR Generic Single Sector Combustor) with the aid of Large Eddy Simulations (LES). An Eulerian description of the continuous phase is adopted and is coupled with a Lagrangian formulation of the dispersed phase. The sub-grid scale (sgs) probability density function approach in conjunction with the stochastic fields solution method is used to account for sgs turbulencechemistry interactions. Stochastic models are used to represent the influence of sgs fluctuations on droplet dispersion and evaporation. Two different test cases are simulated involving reacting and non-reacting conditions. The simulations of the underlying flow field are satisfying in terms of mean statistics and the structure of the flame is captured accurately. Detailed spray simulations are also presented and compared with measurements where the fuel spray model is shown to reproduce the measured SMD and velocity of the droplets accurately.

show abstract

Section: Modelling Of Droplet Dispersion and Evaporationmentioning

confidence: 99%

Large-eddy simulation of spray combustion in a gas turbine combustor

Jones

Marquis

Vogiatzaki

2014

Combustion and Flame

Self Cite

119

View full text Add to dashboard Cite

show abstract

“…Ignoring the SGS contribution to the particle transport (C o = 0) results to a significant underestimation of the mean dispersion variance. The value of a constant dispersion coefficient has no analytical solution, as discussed in the previous section, but it is suggested 37,57 that it lies in the range of 0.5 − 2. For this particular grid spacing, it seems that the C o = 1 would be the most appropriate choice.…”

Section: B Resultsmentioning

confidence: 99%

A dynamic model for the Lagrangian stochastic dispersion coefficient

2013

View full text Add to dashboard Cite

A stochastic sub-grid model is often used to accurately represent particle dispersion in turbulent flows using Large Eddy Simulations. This type of models have a free parameter, the dispersion coefficient, which is not universal and is strongly grid-dependent. In the present paper, a dynamic model for the evaluation of the coefficient is proposed and validated in decaying homogeneous isotropic turbulence. The grid dependence of the static coefficient is investigated in a turbulent mixing layer and compared to the dynamic model. The dynamic model accurately predicts dispersion statistics and resolves the grid-dependence. Dispersion statistics of the dynamically calculated constant are more accurate than any static coefficient choice for a number of grid spacings. Furthermore, the dynamic model produces less numerical artefacts than a static model and exhibits smaller sensitivity in the results predicted for different particle relaxation times.

show abstract

“…The sub-grid scale (SGS) turbulence models in FLUENT employ the Boussinesq hypothesis as in the RANS models. As a strong approach to research large scale coherent structures such as PVC by using spatial filter to equations and it has been widely applied to simulations of non-premixed combustion processes, LES' ability for accurately predicting complicated unsteady phenomenon and exploring gas turbine combustion has been confirmed in a number of studies [4,11,12].…”

Section: Numerical Model and Methodsmentioning

confidence: 99%

“…The advantage makes ignition much easier which then improves combustion efficiency and greatly lowers pollutant emissions. Numerical simulations of swirl burners include CFD (Computational Fluid Dynamics) investigation into turbulent spray breakup, effects of droplet sizes on burning behavior and etc., with Reynolds Averaged Navier-Stokes (RANS) or Large Eddy Simulation (LES) [11][12][13]. In some CFD investigations, the sub-grid scale probability density function approach has been used to account for turbulence-chemistry interactions.…”

Section: Introductionmentioning

confidence: 99%

Large Eddy Simulation Analysis on Confined Swirling Flows in a Gas Turbine Swirl Burner

et al. 2017

View full text Add to dashboard Cite

This paper describes a Large Eddy Simulation (LES) investigation into flow fields in a model gas turbine combustor equipped with a swirl burner. A probability density function was used to describe the interaction physics of chemical reaction and turbulent flow as liquid fuel was directly injected into the combustion chamber and rapidly mixed with the swirling air. Simulation results showed that heat release during combustion accelerated the axial velocity motion and made the recirculation zone more compact. As the combustion was taking place under lean burn conditions, NO emissions was less than 10 ppm. Finally, the effects of outlet contraction on swirling flows and combustion instability were investigated. Results suggest that contracted outlet can enhance the generation of a Central Vortex Core (CVC) flow structure. As peak RMS of velocity fluctuation profiles at center-line suggested the turbulent instability can be enhanced by CVC motion, the Power Spectrum Density (PSD) amplitude also explained that the oscillation at CVC position was greater than other places. Both evidences demonstrated that outlet contraction can increase the instability of the central field.

show abstract

Large Eddy simulation of a droplet laden turbulent mixing layer

Cited by 8 publications

References 35 publications

Large-eddy simulation of spray combustion in a gas turbine combustor

Large-eddy simulation of spray combustion in a gas turbine combustor

A dynamic model for the Lagrangian stochastic dispersion coefficient

Large Eddy Simulation Analysis on Confined Swirling Flows in a Gas Turbine Swirl Burner

Contact Info

Product

Resources

About