Injection of supercritical aviation kerosene fuel into quiescent atmospheric environment

The injection of RP-3 aviation kerosene at conditions near and above the critical point into a quiescent atmospheric environment is experimentally studied, with special emphasis on the effects of fuel injection temperature and pressure on jet characteristics, shock structures, and phase transition. Visualization of the near-field jets and characterization of the shock/jet structures are performed using schlieren imaging. Flow visualization shows fuel condensation phenomenon when supercritical kerosene is injected at reduced temperatures near unity. For the supercritical kerosene injection conditions investigated, ideal gas-like expansion and internal shock structures are observed. The jet expansion angle as well as the axial location and the size of the Mach disk are noted to increase as the injection pressure is increased. Furthermore, while the injection temperature has little effect on the jet structure, it affects the phase transition processes, as demonstrated in the thermodynamic phase diagram calculated using a three-species kerosene surrogate.