Supersonic mixing and combustion: advance in les modeling

Abstract

Mixing and combustion in supersonic reacting flows are currently under investigation for new generation launchers and trans-atmospheric vehicles. Experimental results with hydrogen injected at Mach 2.5 in a Mach 2 airstreams showed combustion taking place just in ∼0.6 m: this indicates that supersonic combustion is feasible within short combustors. Large eddy numerical simulations including the subgrid scale (SGS) model, ISCM, developed specifically for supersonic combustion have been done. This model takes into account the effect of compressibility on reaction rates and on mixing. Numerical simulations have revealed that the §ame is unsteady: it anchors at about 15 cm from the injector, develops downstream, and lifts off. Periodical ignition and quenching have been investigated. Also, the combustion regime in supersonic flows has been investigated and is reported.