Abstract
Large-eddy simulations (LES) have been coupled with a conditional moment closure (CMC) method for the improved modelling of small scale turbulence-chemistry interactions in turbulent spray flames. Partial pre-evaporation of the liquid fuel prior to exiting the injection nozzle requires a modified treatment for the boundary conditions in mixture fraction space and mixture fraction subgrid distribution and conditionally averaged subgrid dissipation need to be known. Different modelling approaches for the subgrid distribution of mixture fraction have been assessed, but the modelling of subgrid scalar dissipation that is responsible for the subgrid fuel transport from the droplet surface towards the cell filtered mean has not been forthcoming. Instead, we introduce a new conditioning method based on two sets of conditional moments conditioned on two differently defined mixture fractions: the first mixture fraction is a fully conserved scalar, the second mixture fraction is based on the fluid mass originating from the liquid fuel stream and is strictly not conserved due to the evaporation process. The two-conditional moment approach is validated by comparison with measurements from a turbulent ethanol spray flame and predicted temperature and velocity profiles could significantly be improved when compared to conventional LES-CMC modelling.
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References
Bilger, R.W.: A mixture fraction framework for the theory and modeling of droplets and sprays. Combust. Flame 158, 191–202 (2011)
Bini, M., Jones, W.: Large eddy simulation of an evaporating acetone spray. Int. J. Heat Fluid Flow 30, 471–480 (2009)
Borghesi, G., Mastorakos, E., Devaud, C.B., Bilger, R.W.: Modeling evaporation effects in conditional moment closure for spray autoignition. Combust. Theory Model. 15(5), 725–752 (2011)
Bottone, F., Kronenburg, A., Gosman, D., Marquis, A.: The numerical simulation of diesel spray combustion with LES-CMC. Flow Turbul. Combust. 89(4), 651–673 (2012)
Chong, C., Hochgreb, S.: Measurements of laminar flame speeds of acetone/methane/air mixtures. Combust. Flame 158(8), 490–500 (2011)
Ge, H.W., Gutheil, E.: Probability density function (pdf) simulation of turbulent spray flows. At. Sprays 16(8), 531–542 (2006)
Kim, W.T., Huh, K.Y.: Numerical simulation of spray autoignition by the first-order conditional moment closure model. Proc. Comb. Inst. 29, 569–576 (2002)
Masri, A.R., Gounder, J.D.: Turbulent spray flames of acetone and ethanol approaching extinction. Combust. Sci. Technol. 182(4), 702–715 (2010)
Mortensen, M., Bilger, R.W.: Derivation of the conditional moment closure equations for spray combustion. Combust. Flame 156, 62–72 (2009)
Navarro-Martinez, S., Kronenburg, A., di Mare, F.: Conditional moment closure for large eddy simulations. Flow Turbul. Combust. 75, 245–274 (2005)
Pera, C., Réveillon, J., Vervisch, L., Domingo, P.: Modeling subgrid scale mixture fraction variance in LES of evaporating spray. Combust. Flame 146, 635–648 (2006)
Réveillon, J., Vervisch, L.: Spray vaporization in nonpremixed turbulent combustion modeling: a single droplet model. Combust. Flame 121, 75–90 (2000)
Rogerson, J.W., Kent, J.H., Bilger, R.W.: Conditional moment closure in a bagasse-fired boiler. Proc. Combust. Inst. 31, 2805–2811 (2007)
Tyliszczak, A., Cavaliere, D., Mastorakos, E.: LES/CMC of blow-off in a liquid fueled swirl burner. Flow Turbul. Combust. 92, 237–267 (2014)
Ukai, S., Kronenburg, A., Stein, O.T.: LES-CMC of a dilute acetone spray flame. Proc. Combust. Inst. 34, 1643–1650 (2013)
Ukai, S., Kronenburg, A., Stein, O.T.: Simulation of dilute acetone spray flames with LES CMC using two conditional moments. Flow Turbul. Combust., 93, 405–423 (2014)
Wright, Y., Margari, O.N., Boulouchos, K., De Paola, G., Mastorakos, E.: Experiments and simulations of n-heptane spray auto-ignition in a closed combustion chamber at diesel engine conditions. Flow Turbul. Combust. 84, 49–78 (2010)
Wright, Y.M., DePaola, G., Boulouchos, K., Mastorakos, E.: Simulations of spray autoignition and flame establishment with two-dimensional CMC. Combust. Flame 143, 402–419 (2005)
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Ukai, S., Kronenburg, A., Stein, O.T. (2015). Certain Aspects of Conditional Moment Closure for Spray Flame Modelling. In: Nagel, W., Kröner, D., Resch, M. (eds) High Performance Computing in Science and Engineering ‘14. Springer, Cham. https://doi.org/10.1007/978-3-319-10810-0_23
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DOI: https://doi.org/10.1007/978-3-319-10810-0_23
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