Numerical Investigation of Dense Turbulent Sprays with an Eulerian Approach and DQMOM

The spray characteristics of the injected liquid fuel predominantly influence the combustion and emissions in IC-engines and gas turbines. This is predetermined by a dense spray region in which droplet-droplet interaction processes play a significant role. In order to accurately describe and control the dense spray behavior in modern engines, an appropriate numerical modeling tool is needed. This contribution aims at including droplet-droplet interactions into an Eulerian approach coupled to the Direct Quadrature Method of Moments (DQMOM) in order to describe evaporating droplet polydispersity and analyze dense turbulent sprays phenomena. Among the advantages of the Eulerian approach are a lower computational cost through optimal parallel computing and a straightforward liquid-gas phase coupling. To assess the designed tool, numerical results are compared to Phase Doppler Anemometry (PDA) measurements of a hollow-cone water spray. The experiment provides comprehensive validation data that include gas velocities, droplet size distribution, droplet mass fluxes and droplet velocities. Turbulence is captured by two different k-ε based models. Preliminary results show that the designed tool is able to capture the process under study in a satisfactory way. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)