Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-19T06:34:12.613Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of the preferential segregation of droplets on evaporation and turbulent mixing

Published online by Cambridge University Press:  04 July 2007

JULIEN REVEILLON  and
FRANCOIS-XAVIER DEMOULIN
JULIEN REVEILLON
Affiliation:
University of Rouen, CORIA UMR-CNRS, 6614, Avenue de l'Université, 76801 Saint Etienne du Rouvray, [email protected]
FRANCOIS-XAVIER DEMOULIN
Affiliation:
University of Rouen, CORIA UMR-CNRS, 6614, Avenue de l'Université, 76801 Saint Etienne du Rouvray, [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Droplet segregation in isotropic homogeneous turbulence is analysed using a spectral direct numerical simulation solver to describe the evolution of the turbulent carrier phase, whose characteristic properties remain statistically stationary due to a semi-deterministic forcing scheme. Lagrangian dilute spray modelling is employed to describe the discrete-phase evolution. The liquid density is distributed on an Eulerian mesh to analyse the evolution of the spray and its spatial distribution. This gives results in accordance with classical methods for droplet segregation. It also allows a deeper analysis of the spray evolution. In particular, droplet segregation and vapour mass fraction may be analysed jointly. First, droplet segregation phenomena are studied through the analysis of the formation and the geometry of the droplet clusters. Then, the effects of segregation on spray evaporation are investigated from both the dispersed and carrier phase points of view. At equilibrium, droplet dynamics leads to different segregation levels that are associated with characteristic Stokes numbers. It appears that the evaporation process evolves in three different stages in time: single-droplet mode in the early stage, cluster mode in the intermediate stage and a gaseous mode in the late stage. Segregation levels strongly affect the evolution of the mean vapour mixture fraction during the second stage, while the corresponding standard deviation is affected for longer, up to the third stage in our simulations. However, from the evolution of the integral scale and the shape of the energy spectrum, it appears that turbulent mixing eliminates the segregation effects, apart from the first evaporation stage when the droplet segregation determines the vapour distribution.

Type
Papers
Information
Journal of Fluid Mechanics , Volume 583 , 25 July 2007 , pp. 273 - 302
Copyright
Copyright © Cambridge University Press 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Aliseda, A., Cartellier, A., Hainaux, F. & Lasheras, J. C. 2002 Effect of preferential concentration on the settling velocity of heavy particles in homogeneous isotropic turbulence. J. Fluid Mech. 468, 77–105.CrossRefGoogle Scholar
Borghi, R. 1988 Turbulent combustion modelling. Prog. Energy Combust. Sci. 14, 245–292.CrossRefGoogle Scholar
Colin, O. & Benkenida, A. 2003 A new scalar fluctuation model to predict mixing in evaporating two-phase flows. Combust. Flame 134, 207–227.CrossRefGoogle Scholar
Crowe, C., Sommerfeld, M. & Tsuji, Y. 1998 Multiphase Flows with Droplets and Particles. CRC Press.Google Scholar
Demoulin, F. X. & Borghi, R. 2002 Modeling of turbulent spray combustion with application to diesel like experiment. Combust. Flame 129, 281–293.CrossRefGoogle Scholar
Elgobashi, S. & Truesdell, G. C. 1992 Direct numerical simulation of particle dispersion in a decaying isotropic turbulence. J. Fluid Mech. 242, 655–700.CrossRefGoogle Scholar
Eswaran, V. & Pope, S. B. 1988 Direct numerical simulations of the turbulent mixing of the passive scalar. Phys. Fluids 31, 506–520.CrossRefGoogle Scholar
Fessler, J. R., Kulick, J. D. & Eaton, J. K. 1994 Preferential concentration of heavy particles in turbulent channel flow. Phys. Fluids 6, 3742–3749.CrossRefGoogle Scholar
Givi, P. 1989 Model free simulations of turbulent reactive flows. Prog. Energy Combust. Sci. 15, 1–107.CrossRefGoogle Scholar
Guichard, L., Reveillon, J. & Hauguel, R. 2004 Direct numerical simulation of statistically stationary one- and two-phase turbulent combustion: a turbulent injection procedure. Flow, Turbulence Combust. 73, 133–167.CrossRefGoogle Scholar
Kerr, R. M. 1981 Theoritical investigation of passive scalar such as temperature in isotropic turbulence. PhD thesis, Cornell University.Google Scholar
Klimenko, A. Y. & Bilger, R. W. 1999 Conditional moment closure for turbulent combustion. Prog. Energy Combust. Sci. 25, 595–687.CrossRefGoogle Scholar
Kuo, K. K. 1986 Principles of Combustion. John Wiley and Sons.Google Scholar
Lee, S., Lele, K. & Moin, P. 1991 Numerical simulations of spatially evolving compressible turbulence. Center for Turbulence Research, Annual Research Briefs, Stanford, 126.Google Scholar
Lele, S. K. 1992 Compact finite difference schemes with spectral like resolution. J. Comput. Phys. 103, 16–42.Google Scholar
Linán, A. & Williams, F. 1993 Fundamentals Aspects of Combustion. Oxford University Press.CrossRefGoogle Scholar
Ling, W., Chung, J. N., Troutt, T. R. & Crowe, C. T 1998 Direct numerical simulation of a three- dimensional temporal mixing layer with particle dispersion. J. Fluid. Mech. 358, 61–85.CrossRefGoogle Scholar
Mantel, T. & Borghi, R. 1994 A new model of premixed wrinkled flame propagation based on a scalar dissipation equation. Combust. and Flame 96, 443–457.CrossRefGoogle Scholar
Mashayek, F. 1998 Direct numerical simulations of evaporating droplet dispersion in forced low Mach number turbulence. Intl J. Heat Mass Transfer 41 (17), 2601–2617.CrossRefGoogle Scholar
Mashayek, F., Jaberi, F. A., Miller, R. S. & Givi, P. 1997 Dispersion and polydispersity of droplets in stationary isotropic turbulence. Intl J. Multiphase Flow 23 (2), 337–355.Google Scholar
Miller, R. S. & Bellan, J. 1999 Direct numerical simulation of a confined three-dimensional gas mixing layer with one evaporating hydrocarbon-droplet-laden stream. J. Fluid Mech. 384, 293–338.Google Scholar
Miller, R. S. & Bellan, J. 2000 Direct numerical simulation and subgrid analysis of a transitional droplet laden mixing layer. Phys. Fluid 12, 650–671.CrossRefGoogle Scholar
Mydlarski, L. & Warhaft, Z. 1998 Passive scalar statistics in high-pclet-number grid turbulence. J. Fluid Mech. 358, 135–175.CrossRefGoogle Scholar
Newman, G. R, Launder, B. E. & Lumley, J. L. 1982 Modeling the behaviour of homogeneous scalar turbulence. J. Fluid Mech. 111, 217–232.Google Scholar
Orszag, S. A. & Patterson, G. S. 1972 Numerical simulation of three-dimensional homogeneous isotropic turbulence. Phys. Rev. Lett. 28 (2), 76–79.CrossRefGoogle Scholar
Overholt, M. R. & Pope, S. B. 1998 A deterministic forcing scheme for direct numerical simulation of turbulence. Computers Fluids 27, 11–28.CrossRefGoogle Scholar
Pantano, C., Sarkar, S. & Williams, F. A. 2003 Mixing of a conserved scalar in a turbulent reacting shear layer. J. Fluid Mech 481, 291–328.Google Scholar
Peters, N. 1986 Laminar flamelet concepts in turbulent combustion. In Proc. 21st Symposium (Intl) on Combustion, pp. 1231–1250. The Combustion Institute.Google Scholar
Poinsot, T., Candel, S. & Trouvé, A. 1996 Direct numerical simulation of premixed turbulent combustion. Prog. Energy Combust. Sci. 12, 531–576.Google Scholar
Poinsot, T. & Veynante, D. 2001 Theoretical and Numerical Combustion. Edwards.Google Scholar
Reveillon, J., Bray, K. N. C. & Vervisch, L. 1998 DNS study of spray vaporization and turbulent micro-mixing. AIAA Paper 98–1028.CrossRefGoogle Scholar
Reveillon, J. & Vervisch, L. 2000 Accounting for spray vaporization in non-premixed turbulent combustion modeling: A single droplet model (SDM). Combust. Flame 1, 75–90.Google Scholar
Reveillon, J. & Vervisch, L. 2005 Analysis of weakly turbulent diluted-spray flames and spray combustion regimes. J. Fluid Mech., 537, 317–347.Google Scholar
Riley, J. J. & Patterson, G. S. Jr, 1974 Diffusion experiments with numerically integrated isotropic turbulence. Phys. Fluids 17, 292–297.Google Scholar
Rogallo, R. S. 1981 Numerical experiments in homogeneous turbulence. NASA, Tech. Mem. 81315.Google Scholar
Samimy, M. & Lele, S. K. 1991 Motion of particles with inertia in a compressible free shear layer. Phys. Fluids 8, 1915–1923.CrossRefGoogle Scholar
Siggia, E. D. & Patterson, G. S. 1978 Intermittency effects in a numerical simulation of stationary three-dimensional turbulence. J. Fluid Mech. 86, 567–592.Google Scholar
Simonin, O., Fevrier, P. & Laviéville, J. 1993 On the spatial distribution of heavy-particle velocities in turbulent flow: from continuous field to particulate chaos. J. Turbulence 118, 97–118.Google Scholar
Sirovich, L. 1991 New perspectives in Turbulence. Springer.Google Scholar
Squires, K. D. & Eaton, J. K. 1991 Preferential concentration of particles by turbulence. Phys. Fluids 3, 1169–1178.Google Scholar
Vervisch, L. & Poinsot, T. 1998 Direct numerical simulation of non-premixed turbulent flame. Annu. Rev. Fluid Mech. 30, 655–692.Google Scholar
Wang, L. P. & Maxey, M. R. 1993 Settling velocity and concentration distribution of heavy particles in homogeneous isotropic turbulence. J. Fluid Mech. 256, 27–68.CrossRefGoogle Scholar