Dynamics of a Fuel Jet Injected into High Temperature and Oxygen Deficient Cross-Flow

Abstract

SUMMARY The combustion characteristics of propane gas jet injected into a cross-flow of high temperature have been examined using a specially designed experimental high temperature air combustion facility. The combustion air could be either normal or reduced oxygen concentration air. The composition and temperature of the combustion air flow can be controlled and varied in order to simulate phenomena that occur in high temperature air combustion conditions. The momentum flux ratio between the fuel jet and the combustion air flow was kept constant to provide similarity between the different experimental cases and to understand the role of fuel jet property on mixing and combustion. Information has been obtained on the global flame features, flowfield and OH, CH and C2 intermediate species during combustion. The results have also been obtained under isothermal case to show the direct role of combustion on the fluid dynamics. The results showed a strong dependence of the oxygen content and air preheats temperature on the fluid dynamics and the spatial distribution of intermediate species from within the flames. The noise emission results showed significantly reduced noise levels under high temperature air combustion conditions. The results showed significant role of the combustion air temperature and oxygen content on mixing, gas jet expansion and combustion. It was found that the mixing is hampered under high temperature air combustion conditions as compared to the normal air case. This resulted in zones of higher axial strain over prolonged distances as compared to the normal temperature air case. The fuel jet penetration into the surrounding combustion air is significantly enhanced under combustion conditions and depends on combustion air properties.