This study focuses on Large Eddy Simulations (LES) in the Eulerian-Lagrangian framework of turbulent spray jets. The choice of the numerical grid relates both to turbulence level description and parcels-grid cells interaction. The objective of the present work is to determine a case setup capable of predicting flow fields of a turbulent n-heptane spray jet for which a set of experimental data in non-reactive conditions (isothermal) is available [21]. The study first focuses on the LES grid, based on simulation with only gas phase, and subsequently on the choice of the suitable number of parcels to describe the spray. The droplets behavior is analyzed using the particle Stokes number at different axial locations. Furthermore, a variation in the existing injection methodology, as available in OpenFOAM R , reveals a beneficial impact on the prediction of the experimental data.

This work concerns numerical simulations of the turbulent H2/N2/air jet diffusion flame (Meier et al., 1996), using Large Eddy Simulations (LES) and Conditional Moment Closure (CMC) as combustion model. The study focuses on the impact of the Random Spots method (Kornev et al., 2007), adopted to describe the turbulence at the inlet, on the flow field. Furthermore the region where the contribution of differential molecular diffusion is relevant is determined through the analysis of the Scalar Dissipation Rate (SDR). The numerical results are discussed 2 through the analysis of Favre-averaged profiles of velocity, mixture fraction temperature and species along the centerline and at three axial locations.

this work concerns numerical simulations of a hydrogen diffusion flame, using Large Eddy Simulations (LES) and Conditional Moment Closure (CMC) as turbulent combustion model. In order to explore the effect of turbulence, two types of inlet boundary conditions are applied: White Noise and a method of Random Spots. The analysis of Favre-averaged profiles of velocity, mixture fraction, temperature and species has led to the conclusion that the method of Random Spots is in much better agreement with the experimental data, as expected. However, several discrepancies between simulations and experiments can also be caused by the boundary conditions applied at the sides and the outlet of the domain.