Abstract:
A
experimental study of the two-phase flow inside a lean premixed prevaporised
combustor has been carried out in order to evaluate the capabilities of large eddy
simulations
applied to engineering applications. To this end, a existing LPP design was
modified in order to
simplify the injection mechanisms involved and gain a optimum
optical access if the critical injection region. The liquid and the gas phase inside the LPP
module are then characterised with the help of non-invasive laser techniques, namely
PDA for the
liquid phase, LDA for the airstream and PLIF for the vapour phase. Relevant
information
regarding droplet sizes, droplet velocity, airstream velocity and fuel
placement have thus been collected. The measurements are then evaluated against flow
solutions
computed by a Eulerian-Lagrangian ite-volume solver. A hybrid
RANS/LES
modelling strategy has been adopted for the gas phase and the Lagrangian
tracking procedure has been updated to predict the influence of the gas turbulence on the
droplet dispersion, and the heat penetrating the droplet during its evaporation. This
simulation is
finally matched against ZD and 3D steady RANS solution in a attempt to
demonstrate the
superiority of the time dependent approach.
