DEFINITION:

Combustion in turbomachines is the mean to introduce energy in the system. The quality of the combustion has a direct influence upon a great number of factors and particularly the pollution through gaseous (NOx, CO, unburned hydrocarbons, …) and soot emissions. The behaviour of the condensed phase (liquid kerosene) has a major impact on the location and the development of combustion and emission. Combustion is of the turbulent type. The accurate prediction of multiphase turbulent combustion supposes the mastering of turbulence itself. In particular, radiation cannot be anymore ignored as it redistributes energy in the volume and thus change the chemical kinetics. So the problem is still very opened and remains strategic considering the particular focus that is made upon pollution. For this study, experimental investigation with sophisticated diagnostic techniques and numerical simulation, averaged or unsteady, remain mandatory. Nitric oxides production being maximum at stoechiometric conditions, combustion processes at lean or rich conditions induce a deep evolution of the combustors. The catalytic combustion is a possible route but the use in aeronautical engines presents some difficulties like lifetime of catalytic substrates.

(Source: ACARE Domain 303)

SUBDOMAINS:

1. Combustion efficiency
2. Injection : atomisation, vaporisation
3. Chemical kinetics
4. Turbulent combustion modelling
5. Radiative transfers
6. Stability
7. Ignition, extinction
8. Instabilities
9. Active control
10. Auto-ignition and flash-back
11. Gaseous emissions
12. Soots
13. Catalytic combustion
14. Diagnostics